Title: Method and device for manufacturing coiled electrode group
Abstract: A positive electrode plate (8), a negative electrode plate (4), and a separator (7) respectively having lengths required for constituting one spiral electrode group (103) are mounted on individual mount jigs (30, 32, 28) for pulling out or for winding, thereby constituting individual cassettes (29, 31, 27). These individual cassettes (29, 31, 27) are sequentially supplied for, and then mounted on a plurality of group winding head units (20) circulating along a predetermined transportation path. The electrode plates (8, 4) and the separator (7) are wound around a rotationally-driven winding shaft (22) of the group winding head unit (20) while the individual electrode plates (8, 4) supplied from the individual electrode plate cassettes (29, 31) are being positioned at predetermined relative positions on both sides of the separator (7) supplied from the separator cassette (27) in a process for circularly transporting the group winding head units (20).
Patent Number: 6,936,080 Issued on 08/30/2005 to Murata, et al.
| Inventors:
|
Murata; Ichiro (Settsu, JP);
Sakoda; Masaki (Hirakata, JP);
Aoi; Takayuki (Hirakata, JP);
Koda; Minoru (Hirakata, JP)
|
| Assignee:
|
Matsushita Electric Industrial Co., Ltd. (Osaka, JP)
|
| Appl. No.:
|
239673 |
| Filed:
|
January 28, 2002 |
| PCT Filed:
|
January 28, 2002
|
| PCT NO:
|
PCT/JP02/00619
|
| 371 Date:
|
September 30, 2002
|
| 102(e) Date:
|
September 30, 2002
|
| PCT PUB.NO.:
|
WO02/06186 |
| PCT PUB. Date:
|
August 8, 2002 |
Foreign Application Priority Data
| Jan 31, 2001[JP] | 2001-024440 |
| Current U.S. Class: |
29/623.1; 29/623.5 |
| Intern'l Class: |
H01M 006/00 |
| Field of Search: |
29/6231,623.5
|
References Cited [Referenced By]
U.S. Patent Documents
| 5718395 | Feb., 1998 | Nakanose et al.
| |
| Foreign Patent Documents |
| 58-010377 | Jan., 1983 | JP.
| |
| 09-147878 | Jun., 1997 | JP.
| |
| 11-336349 | Nov., 1999 | JP.
| |
| 2000/-251919 | Sep., 2000 | JP.
| |
| 2001/-216998 | Aug., 2001 | JP.
| |
| WO 01/3930/4 | May., 2001 | WO.
| |
Primary Examiner: Yuan; Dah-Wei
Attorney, Agent or Firm: Jordan and Hamburg LLP
Claims
1. A method for manufacturing a spiral electrode group for a battery by winding
a belt-shape positive electrode plate and a belt-shape negative electrode plate
in a spiral shape while laminating the positive electrode plate and the negative
electrode plate with a separator interposed therebetween, said method comprising:
forming a first plurality of cassettes with a first jig, each cassette containing
a length of said positive electrode plate to form a single spiral electrode group;
forming a second plurality of cassettes with a second jig, each cassette containing
a length of said negative electrode plate to form a single spiral electrode group;
forming a third plurality of cassettes with a third jig, each cassette containing
a length of said separator to form a single spiral electrode group;
each of said first, second and third cassettes being formed mutually independently;
sequentially supplying a plurality of group winding head units circulating along
a predetermined transportation path with the positive electrode plate cassette,
the negative electrode plate cassette, and the separator cassettes respectively,
thereby mounting these cassettes on the head units;
positioning individual ends of the positive electrode plate and the negative
electrode plate to predetermined relative positions in the process for circularly
transporting said group winding head units, the positive electrode plate and the
negative electrode plate respectively supplied from said positive electrode plate
cassette and said negative electrode plate cassette to predetermined positions
in the lengthwise direction on the both sides of the separator supplied from said
separator cassette; and
winding the positive electrode plate, the negative electrode plate, and the separator
around a rotationally-driven winding shaft of said group winding head unit while
the positive electrode plate, the negative electrode plate, and the separator are
being laminated.
2. The method for manufacturing a spiral electrode group according to claim 1, wherein
the plurality of group winding head units are circulated in one direction along
a circular transportation path, and simultaneously the positive electrode plate
cassette, the negative electrode plate cassette, and the separator cassette are
respectively mounted on the individual group winding head units sequentially transported
to a supply position on said transportation path;
the spiral electrode group is delivered to transportation means at a delivery
position on said transportation path after the spiral electrode group is wound
by said individual group winding head units in the transportation process while
the positive electrode plate and the negative electrode plate are being laminated
with the separator interposed therebetween; and
the individual mount jigs in said positive electrode plate cassette, said negative
electrode plate cassette, and said separator cassette are delivered to transportation
means at a discharge position on said transportation path after respectively having
supplied the positive electrode plate, the negative electrode plate, and the separator.
3. The method for manufacturing a spiral electrode group according to claim 1, wherein
at least either one of the positive electrode plate cassette and the negative
electrode plate cassette is formed by winding the electrode plate with the predetermined
length on an outer peripheral surface of a rotatable drum in one of the electrode
plate mount jigs, and then temporarily fixing a wound end of the electrode plate
against slack; and
the separator cassette respectively winds portions of the separator divided according
to the lengths of the positive electrode plate and the negative electrode plate
on a pair of rotatable winding shafts provided to the separator cassette, thereby
mounting the separator between said pair of winding shafts.
4. The method for manufacturing a spiral electrode group according to claim 3, wherein
the separator cassette is constituted by:
passing the separator through individual engagement slits of the pair of winding
shafts of the separator mount jig while pulling out the separator from a supply
source;
rotationally driving one of the winding shafts for winding up said separator
by a length approximately equivalent to that necessary for constituting one spiral
electrode group; and
cutting a trailing end position of said separator with a cutter, and then driving
the other of the winding shaft to wind said separator by a length corresponding
to the length of the positive electrode plate or the negative electrode plate from
said winding shaft on the one side.
5. An apparatus for manufacturing a spiral electrode group for a battery by winding
a belt-shape positive electrode plate and a belt-shape negative electrode plate
in a spiral shape while laminating the positive electrode plate and the negative
electrode plate with a separator interposed therebetween, said apparatus comprising:
a negative electrode plate cassette formed by winding a negative electrode plate
of said belt-shape electrode plates with a predetermined length by multiple turns
on an outer peripheral surface of a drum supported rotatably, and simultaneously
by maintaining the electrode plate in a wound state on said drum while the electrode
plate is locked by a separable lock member in contact with a wound end of the electrode
plate against slack;
a positive electrode plate cassette for maintaining a positive electrode plate
of said belt-shape electrode plates with the predetermined lengths in a pullable
manner;
a separator cassette including a pair of winding shafts rotatably supported in
parallel with each other, and maintaining the separator while both ends in the
lengthwise direction of the separator with a predetermined length are engaged with
engagement slits formed along the shaft center of said pair of individual winding
shafts, and simultaneously portions of said separator divided according to the
lengths of the positive electrode plate and the negative electrode plate are respectively
wound on said pair of winding shafts; and
a plurality of group winding head units provided for circulating along a circular
transportation path, wherein
a spiral electrode group is formed by sequentially mounting said positive electrode
plate cassette, said negative electrode plate cassette, and said separator cassette
on the individual group winding head units at a supply position on said transportation
path, supplying said positive electrode plate and negative electrode plate to predetermined
positions on both sides of said separator in contact with a winding shaft of said
individual group winding head unit, positioning the ends of said positive electrode
plate and negative electrode plate to predetermined relative positions, and winding
said positive electrode plate, said negative electrode plate, and said separator
on said winding shaft rotationally driven while the positive electrode plate, the
negative electrode plate, and the separator are being laminated in a process of
circulating said group winding head units on said path.
6. An apparatus for manufacturing a spiral electrode group for a battery by winding
a belt-shape positive electrode plate and a belt-shape negative electrode plate
in a spiral shape while laminating the positive electrode plate and the negative
electrode plate with a separator interposed therebetween, said apparatus comprising:
positive and negative electrode plate cassettes formed by respectively winding
the electrode plates with predetermined lengths by multiple turns on outer peripheral
surfaces of drums supported rotatably, and simultaneously maintaining the electrode
plates in a wound state on said drums while the electrode plates are locked by
separable lock members in contact with wound ends of the electrode plates against
slack;
a separator cassette including a pair of winding shafts rotatably supported in
parallel with each other, and maintaining the separator while both ends in the
lengthwise direction of the separator with a predetermined length are engaged with
engagement slits formed along the shaft center of said pair of individual winding
shafts, and simultaneously portions of said separator divided according to the
lengths of the positive electrode plate and the negative electrode plate are respectively
wound on said pair of winding shafts; and
a plurality of group winding head units provided for circulating along a circular
transportation path, wherein
a spiral electrode group is formed by sequentially mounting said positive electrode
plate cassette said negative electrode plate cassette, and said separator cassette
on the individual group winding head units at a supply position on said transportation
path, supplying said positive electrode plate and negative electrode plate to predetermined
positions on both sides of said separator in contact with a winding shaft of said
individual group winding head unit, positioning the ends of said positive electrode
plate and negative electrode plate to predetermined relative positions, and winding
said positive electrode plate, said negative electrode plate, and said separator
on said winding shaft rotationally driven while the positive electrode plate, the
negative electrode plate, and the separator are being laminated in a process of
circulating said group winding head units on said path.
7. The apparatus for manufacturing a spiral electrode group according to 6, wherein
a bottom end of the winding shaft of the group winding head unit is connected
with a driving source in a support tube, a top end of the winding shaft is rotatably
supported by a winding shaft bearing, and the winding shaft comprises a winding
core in contact with a predetermined middle position in the lengthwise direction
of the separator supplied from the separator cassette mounted on said group winding
head unit, and an auxiliary pin protruding from said support tube after the winding
core comes in contact with the separator, and then holding the predetermined middle
position in the lengthwise direction of said separator from both sides along with
said winding core.
8. The apparatus for manufacturing a spiral electrode group according to claim
5, wherein
each of the group winding head units comprises:
a motor for rotationally driving the winding shaft; and
a controller for respectively controlling the operation of the positive electrode
plate cassette, the negative electrode plate cassette, and the separator cassette
mounted on said group winding head unit, and for controlling the rotation of said
motor,
said group winding head unit is constituted such that said controller controls
said motor to start rotation of said winding shaft when the winding shaft comes
in contact with the separator in said separator cassette, controls to bring the
negative electrode plate wound on the drum of the negative electrode plate cassette
in contact with said separator wound on said winding shaft with a predetermined
pressure, thereby adhering a positioning tape provided at the leading end of said
negative electrode plate to said separator with adhesiveness of the positioning
tape, and feeds the end of the positive electrode plate pulled out from the positive
electrode plate cassette between said winding shaft and said separator wound on
said winding shaft, and a friction force acting between said negative electrode
plate and said separator rotates said drum together in synchronism with said winding
shaft.
9. The apparatus for manufacturing a spiral electrode group according to claim
5, wherein
the negative electrode plate cassette for winding the negative electrode plate
includes a support shaft rotatably supported between a pair of facing support bases,
said support shaft externally engaging the drum for winding said electrode plate
on the outer peripheral surface, thereby rotatably supporting the drum between
said support bases, a lock lever pressed by an elastic member against the wound
end of said electrode plate wound on said drum, and an action piece protruded from
the lock lever for receiving a rotation force toward a direction departing from
said drum when said negative electrode plate cassette is mounted on the group winding
head unit; and
said group winding head unit includes a cassette support lever for mounting said
negative electrode plate cassette on one end, said cassette support lever rotating
about a lever support pin as a fulcrum, and an elastic member suspended on the
other end of this cassette support lever, said elastic member for rotating and
urging said cassette support lever so as to press the electrode plate wound on
the drum of said negative electrode plate cassette against the winding shaft or
the separator wound on the winding shaft.
10. The apparatus for manufacturing a spiral electrode group according to claim
5, wherein
the positive electrode plate cassette includes a constitution for holding the
positive electrode plate in an electrode plate mount jig, and for sliding said
positive electrode plate to a predetermined position close to the group winding
head unit; and
said group winding head unit includes: a holding pad for extracting said positive
electrode plate from said electrode plate mount jig while holding said positive
electrode plate slid to said predetermined position, and then inserting the end
of said positive electrode plate between a pair of feeding guide rollers; a chuck
member for chucking to hold said positive electrode plate held by the holding pad;
and an elastic member for urging said chuck member toward a backward direction
of said chuck member.
11. The apparatus for manufacturing a spiral electrode group according to claim
5, further comprising:
a positive electrode plate processing mechanism, a negative electrode plate processing
mechanism, and a separator processing mechanism for respectively constituting the
positive electrode plate cassette the negative electrode plate cassette, and the
separator cassette by respectively mounting or winding the positive electrode plate,
the negative electrode plate, and the separator with the predetermined lengths
on a positive electrode plate mount jig, a negative electrode plate mount jig,
and a separator mount jig; and
a work table including the plurality of group winding head units along a circular
outer peripheral end thereof, and being rotated to circulate the individual group
winding head units along the circular transportation path, wherein
said transportation path includes the supply position for mounting the positive
electrode plate cassette, the negative electrode plate cassette, and the separator
cassette respectively transported from the positive electrode plate processing
mechanism, the negative electrode plate processing mechanism, and the separator
processing mechanism on said individual group winding head units, and a discharge
position for transporting the empty positive electrode plate mount jigs, negative
electrode plate mount jig, and separator mount jig respectively having supplied
the positive electrode plate, the negative electrode plate, and the separator to
transportation mechanisms for transporting to said individual processing mechanisms.
12. The apparatus for manufacturing a spiral electrode group according to claim
6, wherein
each of the group winding head units comprises:
a motor for rotationally driving the winding shaft; and
a controller for respectively controlling the operation of the positive electrode
plate cassette, the negative electrode plate cassette, and the separator cassette
mounted on said group winding head unit, and for controlling the rotation of said
motor,
said group winding unit is constituted such that said controller controls said
motor to start rotation of said winding shaft when the winding shaft comes in contact
with the separator in said separator cassette, and controls to bring the positive
electrode plate and the negative electrode plate wound on the drums of the pair
of electrode plate cassettes in contact with said separator wound on said winding
shaft with a predetermined pressure, thereby adhering positioning tapes provided
at the ends of said electrode plates to said separator with adhesiveness of the
positioning tapes, and friction force acting between said electrode plates and
said separator rotates said drums together with said winding shaft.
13. The apparatus for manufacturing a spiral electrode group according to claim
6, wherein
the pair of electrode plate cassettes for respectively winding the positive electrode
plate and the negative electrode plate includes: a support shaft rotatably supported
between a pair of facing support bases, said support shaft externally engaging
the drum for winding said electrode plate on the outer peripheral surface, thereby
rotatably supporting the drum between said support bases; a lock lever pressed
by an elastic member against the wound end of said electrode plate wound on said
drum; and an action piece protruded from the lock lever for receiving a rotation
force toward a direction departing from said drum when said electrode plate cassettes
are mounted on the group winding head units, and
said group winding head unit includes: a plurality of cassette support levers
for mounting said electrode plate cassette on one end, said cassette support lever
rotating about a lever support pin as a fulcrum; and elastic members individually
suspended on the other end of the plurality of cassette support levers, said elastic
members for rotating and urging said cassette support levers so as to press the
electrode plates wound on the drum of said electrode plate cassettes against the
winding shaft or the separator wound on the winding shaft.
14. The apparatus for manufacturing a spiral electrode group according to claim
6, further comprising:
a positive electrode plate processing mechanism, a negative electrode plate processing
mechanism, and a separator processing mechanism for respectively constituting the
positive electrode plate cassette, the negative electrode plate cassette, and the
separator cassette by respectively mounting or winding the positive electrode plate,
the negative electrode plate, and the separator with the predetermined lengths
on a positive electrode plate mount jig, a negative electrode plate mount jig,
and a separator mount jigs; and
a work table including the plurality of group winding head units along a circular
outer peripheral end thereof, and being rotated to circulate the individual group
winding head units along the circular transportation path, wherein
said transportation path includes the supply position for mounting the positive
electrode plate cassette, the negative electrode plate cassette, and the separator
cassette respectively transported from the positive electrode plate processing
mechanism, the negative electrode plate processing mechanism, and the separator
processing mechanism on said individual group winding head units, and a discharge
position for transporting the empty positive electrode plate mount jig, negative
electrode plate mount jig, and separator mount jig respectively having supplied
the positive electrode plate, the negative electrode plate, and the separator to
transportation mechanisms for transporting to said individual processing mechanisms.
15. The apparatus for manufacturing a spiral electrode group according to 14, wherein
the separator processing mechanism includes:
a tensioning member for applying a required tension to the separator fed out
from a supply source, and being held by guide members at the leading end thereof;
a pair of driving shafts to be connected with the pair of winding shafts for
transmitting rotation when the separator mount jig is held at a predetermined position;
a chuck member for passing the separator through the individual engagement slits
of said pair of the winding shafts while pulling out the separator held by said
guide members after chucking the end of the separator; and
a cutter for cutting said separator, and
one of the winding shafts driven rotationally winds said separator by a length
approximately corresponding to a length required for constituting one spiral electrode
group after the separator is passed through the individual engagement slits of
said pair of the winding shafts, said cutter cuts said separator at a neighborhood
close to the position held by said guide members, and then the other of the winding
shafts driven rotationally winds said separator by a length approximately corresponding
to a length of the positive electrode plate or the negative electrode plate from
said one winding shaft.
16. A method for manufacturing a spiral electrode group for a battery by winding
a belt-shape positive electrode plate and a belt-shape negative electrode plate
in a spiral shape while laminating the positive electrode plate and the negative
electrode plate with a separator interposed therebetween, said method comprising:
constituting a positive electrode plate cassette, a negative electrode plate
cassette, and a separator cassette by mounting the positive electrode plate, the
negative electrode plate, and the separator with lengths necessary for constituting
one spiral electrode group respectively on a positive electrode plate mount jig,
a negative electrode plate mount jig, and a separator mount jig for pulling out,
or for winding;
sequentially supplying a plurality of group winding head units circulating along
a predetermined transportation path with the positive electrode plate cassette,
the negative electrode plate cassette, and the separator cassette respectively,
thereby mounting these cassettes on the head units;
positioning individual ends of the positive electrode plate and the negative
electrode plate to predetermined relative positions in the process for circularly
transporting said group winding head units, the positive electrode plate and the
negative electrode plate respectively supplied from said positive electrode plate
cassette and said negative electrode plate cassette to predetermined positions
in the lengthwise direction on the both sides of the separator supplied from said
separator cassette;
winding the positive electrode plate, the negative electrode plate, and the separator
around a rotationally-driven winding shaft of said group winding head unit while
the positive electrode plate, the negative electrode plate, and the separator are
being laminated;
the plurality of group winding head units are circulated in one direction along
a circular transportation path, and simultaneously the positive electrode plate
cassette, the negative electrode plate cassette, and the separator cassette are
respectively mounted on the individual group winding head units sequentially transported
to a supply position on said transportation path;
the spiral electrode group is delivered to transportation means at a delivery
position on said transportation path after the spiral electrode group is wound
by said individual group winding head units in the transportation process while
the positive electrode plate and the negative electrode plate are being laminated
with the separator interposed therebetween; and
the individual mount jigs in said positive electrode plate cassette, said negative
electrode plate cassette, and said separator cassette are delivered to transportation
means at a discharge position on said transportation path after respectively having
supplied the positive electrode plate, the negative electrode plate, and the separator.
17. A method for manufacturing a spiral electrode group for a battery by winding
a belt-shape positive electrode plate and a belt-shape negative electrode plate
in a spiral shape while laminating the positive electrode plate and the negative
electrode plate with a separator interposed therebetween, said method comprising:
constituting a positive electrode plate cassette, a negative electrode plate
cassette, and a separator cassette by mounting the positive electrode plate, the
negative electrode plate, and the separator with lengths necessary for constituting
one spiral electrode group respectively on a positive electrode plate mount jig,
a negative electrode plate mount jig, and a separator mount jig for pulling out,
or for winding;
sequentially supplying a plurality of group winding head units circulating along
a predetermined transportation path with the positive electrode plate cassette,
the negative electrode plate cassette, and the separator cassette respectively,
thereby mounting these cassettes on the head units;
positioning individual ends of the positive electrode plate and the negative
electrode plate to predetermined relative positions in the process for circularly
transporting said group winding head units, the positive electrode plate and the
negative electrode plate respectively supplied from said positive electrode plate
cassette and said negative electrode plate cassette to predetermined positions
in the lengthwise direction on the both sides of the separator supplied from said
separator cassette;
winding the positive electrode plate, the negative electrode plate, and the separator
around a rotationally-driven winding shaft of said group winding head unit while
the positive electrode plate, the negative electrode plate, and the separator are
being laminated;
at least either one of the positive electrode plate cassette and the negative
electrode plate cassette is formed by winding the electrode plate with the predetermined
length on an outer peripheral surface of a rotatable drum in one of the electrode
plate mount jigs, and then temporarily fixing a wound end of the electrode plate
against slack; and
the separator cassette respectively winds portions of the separator divided according
to the lengths of the positive electrode plate and the negative electrode plate
on a pair of rotatable winding shafts provided to the separator cassette, thereby
mounting the separator between said pair of winding shafts.
18. The method for manufacturing a spiral electrode group according to claim
17, wherein
the separator cassette is constituted by:
passing the separator through individual engagement slits of the pair of winding
shafts of the separator mount jig while pulling out the separator from a supply
source;
rotationally driving one of the winding shafts for winding up said separator
by a length approximately equivalent to that necessary for constituting one spiral
electrode group; and
cutting trailing end position of said separator with a cutter, and then driving
the other of the winding shaft to wind said separator by a length corresponding
to the length of the positive electrode plate or the negative electrode plate from
said winding shaft on the one side.
Description
TECHNICAL FIELD
The present invention relates to a method and an apparatus for manufacturing
a spiral electrode group which is used for a lithium primary battery, for example,
and is constituted by winding a positive electrode plate, a negative electrode
plate, and a separator interposed therebetween in a spiral shape while they are
being laminated.
BACKGROUND ART
Small, high-capacity, and cylindrical lithium primary batteries, and various
types of rechargeable batteries have been used as a drive power supply for portable
electric devices such as a camera. A higher voltage and a higher capacity are required
for these batteries as the portable electric devices have higher performance and
more sophisticated functions. To satisfy these requirements, batteries constituted
by a spiral electrode group formed by winding laminated positive electrode plate,
negative electrode plate, and separator interposed therebetween into a spiral shape
are widely and generally used. For securing high performance and uniform quality
as well as increasing productivity of the spiral electrode group for the various
types of cylindrical batteries, it is important to wind the electrode plates and
the separator in a spiral shape while eliminating a winding displacement between
the positive and negative electrode plates and the separator, preventing an elongated
state caused by an abnormally strong tensile force applied on the electrode plates
and the separator, and avoiding slack of the electrode plates and the separator.
In view of the foregoing, the present applicant previously proposed an apparatus
for manufacturing a spiral electrode group with the high performance and the uniform
quality described above (see Japanese Patent Laid-Open Publication No. Hei. 09-147878).
In this manufacturing apparatus, a belt-shape separator is divided into a first
region on one side and a second region on the other side at the center. The first
region is held between positive and negative electrode plates. A winding shaft
engaged at a boundary between both the regions folds the separator into two so
as to wind the electrode plates and the separator into a spiral shape while the
first and second regions are respectively sucked by first and second suction means.
Thus, the spiral electrode group is manufactured while feeding means are moving
the first and second regions sucked and held by individual endless belts of the
first and second suction means toward the winding shaft from the both sides, thereby
preventing an excessive tensile force from being applied to the separator and the
like constituting the spiral electrode group, and simultaneously rotational feeding
speeds of the endless belts are being controlled so as to optimize the tensile
force, thereby enabling to manufacture a spiral electrode group while preventing
a generation of elongation of the separator and the like, and a generation of displaced
winding between the positive and negative electrode plates.
When this apparatus for manufacturing a spiral electrode group is used for manufacturing
a spiral electrode group for a nickel-cadmium battery or a nickel-metal hydride
battery, since positive and negative electrode plates have relatively large tensile
strength, and high resistance against a tensile force applied in winding, and separator,
which tends to undergo the influence from the tensile force most, has a certain
degree of resistance against and recoverability from elongation in both of these
types of batteries, a relatively excellent spiral electrode group can be obtained.
However, when a spiral electrode group for a cylindrical lithium primary battery
and the like is manufactured, since a lithium metal foil tape in a belt shape constituting
a negative electrode plate has extremely small resistance against a tensile force,
the tape tends to generate a plastic deformation, thereby being elongated by a
slight tensile force, resulting in a change in the shape and the dimension of the
spiral electrode group. Thus, a battery using this spiral electrode group generates
a decrease and a variation of battery characteristics.
On the other hand, the lithium metal foil tape may be wound while a tensile force
is hardly applied to the tape. However, since the belt-shape lithium metal foil
tape has a very soft surface, and thus the tape tends to present a plastic deformation,
when the tape is pressed to or slid on the surface of the metal in a contact state,
the tape tends to adhere to the surface of various types of metal. Thus, the constitution
of the manufacturing apparatus described above cannot securely wind a thin belt-shape
lithium metal foil tape without applying a tensile force, and generating slack.
As a result, since a manufactured spiral electrode group is very loosely wound
as an electrode group, the electrode group is so unstable to present a change in
the shape and the dimension, thereby causing a tendency of a displacement in the
winding. Thus, the present applicant previously proposed an apparatus for manufacturing
a spiral electrode group which winds constituting materials while automatically
adjusting the feeding speed variably to an optimal one which does not apply an
unnecessarily high tensile force according to a variation in thickness of the materials
such as electrode plates (Japanese Patent Laid-Open Publication No. Hei. 11-336349).
In this manufacturing apparatus, as shown in a schematic front view in FIG. 11,
a rotation table 1 including three winding cores 2 provided on the
outer periphery at an interval of 120° rotates by an intermittent increment
of 120° in a direction indicated by an arrow in the drawing, thereby sequentially
moving the three winding cores 2 for positioning to a winding position P
where the winding core 2 comes in contact with a tape suction drum 3.
The winding core 2 is rotationally driven at the winding position P to wind
a negative electrode plate 4, a separator 7, and a positive electrode
plate 8 in a spiral shape while receiving the negative electrode plate 4
from the tape suction drum 3, thereby manufacturing a spiral electrode group 9.
Linear guides 10 are respectively provided between the individual neighboring
two winding cores 2 of the three winding cores 2. A guiding chuck
member 11 and a positioning chuck member (not shown) are respectively provided
so as to smoothly slide with almost no slide load received on the individual guides
10. The guiding chuck member 11 chucks an end of the separator 7
so as to pass through an engagement slit (not shown) in the winding core 2.
The positioning chuck member chucks an end of the positive electrode plate 8
while the positive electrode plate 8 is laminated on, and positioned with
respect to the separator 7, and then feeds the positive electrode plate
8 in a predetermined positioned state with respect to the negative electrode
plate 4 to the winding core 2 while the positioning chuck member
is sliding on the guide 10 as the separator 7 being wound on the
winding core 2 is transported. When the winding core 2 rotates for
winding, the guiding chuck member 11 on the left side with respect to the
winding core 2 in the drawing moves upward along the guide 10 as
the winding core 2 rotates for winding, thereby serving for the winding
core 2 as a weight for applying a proper tensile force to the separator
7. Similarly, the guiding chuck member 11 on the right side with
respect to the winding core 2 in the drawing serves for the winding core
2 as a weight for applying a proper tensile force to the positive electrode
plate 8.
On the other hand, the plurality of tape suction drums 3 are provided at
an equal interval on an outer periphery of a transporting rotation drum (not shown),
and are not connected with a rotationally driving source, but are rotatably supported
by rotation support shaft 12. Simultaneously, an extremely weak braking
force as large as preventing a continuous rotation by an inertia force is applied
to the tape suction drums 3. The negative electrode plate 4, which
is formed as a thin belt-shape lithium metal foil tape, and is cut into a predetermined
length required for constituting the one spiral electrode group 9, is sucked
and held on the outer peripheral surface of the tape suction drum 3 in advance
in a wound state. Simultaneously, the tape suction drums 3 are sequentially
transported to the winding position P by an intermittent rotation of the transporting
rotation drum, and then is pressed against the winding core 2 with a proper
force by a drum support lever 14 rotated and urged by a helical spring 13
toward a direction indicated by an arrow in the drawing.
In this manufacturing apparatus, when the winding core 2 rotates, the tape
suction drum 3 in contact with the winding core 2 is rotated together
in synchronism with the winding core 2 only by a friction force generated
by the contact with the winding core 2. As a result of the rotation, the
negative electrode plate 4 sucked and held on the outer peripheral surface
of the tape suction drum 3 is wound together with portions of the separator
7. Thus, since a tensile force is hardly applied to the negative electrode
plate 4 sucked and held on the tape suction drum 3 supported rotatably,
though the negative electrode plate 4 is a thin lithium metal foil tape,
it is not elongated. Also,- since the tape suction drum 3 rotates through
the drum support lever 14 as the diameter of the spiral electrode group
9 changes, the rotation speed of the tape suction drum 3 automatically
increases so as to be always variably adjusted to a stable optimal value as the
diameter of the spiral electrode group 9 increases though the winding core
2 always rotates at a constant speed. As a result, since a tensile force
is hardly applied to the negative electrode plate 4 in the winding process
for the spiral electrode group 9, the negative electrode plate 4
is not elongated.
In the manufacturing apparatus described above, the tape suction drum 3
rotatably supported is rotated together in synchronism with the winding core 2
by the friction force acting between the negative electrode plate 4 sucked
and held on the outer peripheral surface of the tape suction drum 3 and
the outer peripheral surface of the winding core 2 or the separator 7,
though the negative electrode plate 4 is a thin lithium metal foil tape,
it is not elongated. Thus, the spiral electrode group 9 with a required
shape is surely manufactured. However, this manufacturing apparatus is not proper
for mass-producing the spiral electrode group 9 at high productivity.
Namely, in this manufacturing apparatus, the negative electrode plate 4
is cut into a predetermined dimension after a positioning tape and a negative electrode
lead are attached at a negative electrode plate supplying part (not shown) additionally
provided for this apparatus, the separator 7 is cut into a predetermined
dimension at a separator supplying part additionally provided for the apparatus,
and the positive electrode plate 8 is cut into a predetermined dimension
after a positive electrode lead is attached at a positive electrode plate supply
part additionally provided for the apparatus. Then, after the negative electrode
plate 4, the separator 7, and the positive electrode plate 8
are supplied so as to have required relative positions with respect to the winding
core 2 transported to the single winding position P, the winding is conducted
at this winding position P. In this way, in this manufacturing apparatus, the individual
constituting materials for the spiral electrode group 9 are supplied at
the single winding position P so as to be assembled at the predetermined relative
positions after these materials are made into the predetermined shapes at the individual
supplying parts additionally provided for this apparatus, and then these materials
are wound into the spiral shape. Thus, it is not possible to supply the positive
electrode plate 8, the negative electrode plate 4, and the separator
7 until a next winding core 2 is transported to the winding position
P after one spiral electrode group 9 has been manufactured at the winding
position P. Thus, the increase of the productivity is limited.
In addition, this manufacturing apparatus is constituted such that the negative
electrode plate 4 with a predetermined length required for constituting
one spiral electrode group 9 is maintained in the wound state on the tape
suction drum 3 while the entire part in the lengthwise direction is vacuum-sucked.
Simultaneously the separator 7 is wound by the winding core 2 while
the proper tensile force is applied to the separator 7 by slidingly moving
the guiding chuck members 11 along the guides 10 after the both ends
of the separator 7 with a predetermined length for constituting one spiral
electrode group 9 are chucked by the guiding chuck members 11. Thus,
in this manufacturing apparatus, since it is necessary to use the tape suction
drum 3 with a diameter corresponding to the length of the negative electrode
plate 4, and the guides 10 with a length corresponding to the length
of the separator 7, the apparatus should be a dedicated apparatus for manufacturing
a spiral electrode group 9 for a specific battery. Consequently, it is necessary
to individually prepare the apparatuses for the different types of spiral electrode
groups different in length and width of the positive electrode plate 8,
the negative electrode plate 4, and the separator 7, resulting in
increasing the cost.
The present invention is devised in light of the foregoing, and an object of
the invention is to provide a manufacturing method and a manufacturing apparatus
for highly precisely and highly productively manufacturing various spiral electrode
groups different in length and width of the positive and negative electrode plates
and the separator on a single apparatus.
DISCLOSURE OF THE INVENTION
To attain the object above, a method for manufacturing a spiral electrode group
of the present invention includes: constituting a positive electrode plate cassette,
a negative electrode plate cassette, and a separator cassette by mounting a positive
electrode plate, a negative electrode plate, and a separator with lengths necessary
for constituting one spiral electrode group respectively on appositive electrode
plate mount jig, a negative electrode plate mount jig, and a separator mount jig
for pulling out, or for winding; sequentially supplying a plurality of group winding
head units circulating along a predetermined transportation path with the positive
electrode plate cassette, the negative electrode plate cassette, and the separator
cassette respectively, thereby mounting these cassettes on the head units; positioning
individual ends of the positive electrode plate and the negative electrode plate
to predetermined relative positions in the process for circularly transporting
the group winding head units, the positive electrode plate and the negative electrode
plate respectively supplied from the positive electrode plate cassette and the
negative electrode plate cassette to predetermined positions in the lengthwise
direction on the both sides of the separator in the separator cassette; and winding
the positive electrode plate, the negative electrode plate, and the separator around
a rotationally-driven winding shaft of the group winding head unit while the positive
electrode plate, the negative electrode plate, and the separator are being laminated.
In this method for manufacturing a spiral electrode group, after both of the
electrode
plates and the separator are constituted as the cassettes for pulling out or winding,
and then these individual cassettes are sequentially mounted on the plurality of
group winding head units circulating along the transportation path, the individual
units wind both of the electrode plates and the separator while they are being
laminated in the process of circulating the plurality of group winding head units
along the transportation path, thereby manufacturing spiral electrode groups. Thus,
since the spiral electrode groups are simultaneously wound at a plurality of locations,
the productivity increases remarkably compared with a case where the spiral electrode
group is wound at a single location.
An apparatus for manufacturing a spiral electrode group of the present invention
includes: a negative electrode plate cassette formed by winding one electrode plate
of belt-shape electrode plates with predetermined lengths by multiple turns on
an outer peripheral surface of a drum supported rotatably, and simultaneously by
maintaining the electrode plate in a wound state on the drum while the electrode
plate is locked by a separable lock member in contact with a wound end of the electrode
plate against slack; a positive electrode plate cassette for holding the other
electrode plate of the belt-shape electrode plates with the predetermined lengths
in a pullable manner; a separator cassette which includes a pair of winding shafts
which are rotatably supported in parallel with each other, and maintains a separator
while both ends in the lengthwise direction of the separator with a predetermined
length are engaged with engagement slits formed along the shaft center of the pair
of individual winding shafts, and simultaneously portions of the separator divided
according to the lengths of the positive electrode plate and the negative electrode
plate are respectively wound on the pair of winding shafts; and a plurality of
group winding head units provided for circulating along a circular transportation
path. The manufacturing apparatus is constituted such that a spiral electrode group
is formed by sequentially mounting the positive electrode plate cassette, the negative
electrode plate cassette, and the separator cassette on the individual group winding
head units at a supply position on the transportation path, supplying the positive
electrode plate and negative electrode plate to predetermined positions on the
both sides of the separator in contact with the winding shaft of the individual
group winding head unit, positioning ends of the positive electrode plate and negative
electrode plate to predetermined relative positions, and winding the positive electrode
plate, the negative electrode plate, and the separator on the winding shaft rotationally
driven while the positive electrode plate, the negative electrode plate, and the
separator are being laminated in a process of circulating the group winding head
units on the path.
An alternative apparatus for manufacturing a spiral electrode group of the present
invention includes: positive and negative electrode plate cassettes formed by winding
electrode plates with predetermined lengths by multiple turns on an outer peripheral
surface of drums supported rotatably, and simultaneously by maintaining the electrode
plates in the wound state on the drums while the electrode plates are locked by
separable lock members in contact with a wound end of the electrode plates against
slack; a separator cassette which includes a pair of winding shafts rotatably supported
in parallel with each other, and maintains the separator while both ends in the
lengthwise direction of the separator with a predetermined length are engaged with
engagement slits formed along the shaft center of the pair of individual winding
shafts, and simultaneously portions of the separator divided according to the lengths
of the positive electrode plate and the negative electrode plate are respectively
wound on the pair of winding-shafts; and a plurality of group winding head units
provided for circulating along a circular transportation path. The manufacturing
apparatus is constituted such that a spiral electrode group is formed by sequentially
mounting the positive electrode plate cassette, the negative electrode plate cassette,
and the separator cassette on the individual group winding head units at a supply
position on the transportation path, supplying the positive electrode plate and
negative electrode plate to predetermined positions on the both sides of the separator
in contact with a winding shaft of the individual group winding head unit, positioning
the ends of the positive electrode plate and negative electrode plate to predetermined
relative positions, and winding the positive electrode plate, the negative electrode
plate, and the separator on the winding shaft rotationally driven while the positive
electrode plate, the negative electrode plate, and the separator are being laminated
in a process of circulating the group winding head units on the path.
In these apparatuses for manufacturing a spiral electrode group, the electrode
plate cassettes and the separator cassette are easily mounted on the group winding
head unit, and simultaneously a spiral electrode group is manufactured at high
precision by interposing the separator between the electrode plates smoothly pulled
out from the electrode plate cassettes while the separator is being wound on the
winding shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a principal part showing a manufacturing apparatus
embodying a method for manufacturing a spiral electrode group according to a first
embodiment of the present invention;
FIG. 2A, FIG. 2B, and FIG. 2C are perspective views respectively showing a separator
mount jig, a negative electrode plate mount jig, and a positive electrode plate
mount jig used for this manufacturing apparatus;
FIG. 3 is a schematic front view showing an overall constitution of a negative
electrode plate processing mechanism for this manufacturing apparatus;
FIG. 4A to FIG. 4C are process drawings arranged in the order of process, and
schematically showing a manufacturing process for constituting a separator cassette
at a separator processing mechanism for this apparatus;
FIG. 5 is a perspective view showing a relative positional relationship among
a positive electrode plate cassette, a negative electrode plate cassette, and the
separator cassette supplied for a group winding head unit in this apparatus;
FIG. 6 is a schematic plan view for the state in FIG. 5;
FIG. 7 is a schematic plan view showing a state where a winding shaft is rotated
by half a turn in this apparatus;
FIG. 8A is a schematic explanatory drawing showing a relative positional relationship
among the positive electrode plate, the negative electrode plate, and the separator
in a developed state in this apparatus when the winding shaft starts winding, FIG.
8B is an enlarged view of a neighborhood of the winding shaft in FIG. BA;
FIG. 9 is a schematic plan view for a state immediately before the completion
of manufacturing the spiral-shape electrode group in this apparatus;
FIG. 10 is a schematic plan view showing a relative positional relationship
among a positive electrode plate cassette, a negative electrode plate cassette,
and a separator cassette supplied for a group winding head unit for an apparatus
for manufacturing a spiral electrode group according to another embodiment of the
invention; and
FIG. 11 is a schematic front view showing a conventional apparatus for manufacturing
a spiral electrode group.
BEST MODE FOR CARRYING OUT THE INVENTION
The following section describes preferred embodiments of the present invention
while referring to drawings. FIG. 1 is a perspective view of a principal part showing
a manufacturing apparatus embodying a method for manufacturing a spiral electrode
group according to a first embodiment of the invention. This embodiment exemplifies
the apparatus for manufacturing a spiral electrode group for a lithium primary battery.
In this drawing, this manufacturing apparatus includes a rotating support pillar
18 which is erected on an apparatus base
17, and is rotated in a
direction indicated by an arrow in the drawing, a work table
19 which is
fixed to a lower outer peripheral surface of the rotating support pillar
18,
and integrally rotates with the pillar
18, and a plurality (such as
16)
of group winding head units
20 provided at an equal interval along the outer
peripheral end of the work table
19. The group winding head unit
20
is constituted by a servomotor (a drive source)
21 provided on a bottom
surface of the work table
19, a winding shaft
22 which is erected
on the top surface of the work table
19, and is rotationally driven by the
servomotor
21, and other elements. A plurality of servo controllers
24
for individually controlling the servomotors
21 for the individual group
winding head units
20 are provided on a support shelf
23 fixed to
an upper part of the rotating support pillar
18. Thus, the plurality of
group winding head units
20 circulate along a circular transportation path
as the work table
19 rotates intermittently.
When the individual group winding head units
20 reach a predetermined
position as the work table
19 rotates, a separator cassette
27 formed
by winding a separator
7 with a predetermined length required for constituting
one spiral electrode group on a separator mount jig
28, a positive electrode
plate cassette
29 formed by mounting a positive electrode plate
8
with a predetermined length required for constituting one spiral electrode group
to a positive electrode plate mount jig
30, and a negative electrode plate
cassette
31 formed by winding a negative electrode plate
4 made of
a thin lithium metal foil tape with a predetermined length required for constituting
one spiral electrode group on a negative electrode plate mount jig
32 are
individually supplied.
A chuck member of a robot mechanism (not shown) transports the supplied positive
electrode plate
8 so as to be sucked and held by the positive electrode
plate mount jig
30 after the positive electrode plate
8 is processed
into a state ready for constituting one spiral electrode group by cutting into
the predetermined length, and by attaching a positive electrode lead
34
to a predetermined position in a positive electrode plate processing mechanism
33. Then, the positive electrode plate
8 and the positive electrode
plate mount jig
30 are supplied as the positive electrode plate cassette
29 for the group winding head unit
20. Since the positive electrode
plate
8 constituting the spiral shape electrode group for a lithium primary
battery manufactured in the present embodiment is constituted by a ferromagnetic
stainless steel as a core material, and the positive electrode plate
8 has
a relatively high stiffness, the positive electrode plate
8 is easily handled
as a plate-shape member, and simultaneously can be transported while magnetically
attached by a magnet as described later. These are the reasons for constituting
the positive electrode plate cassette
29 in this way.
After the separator cassette
27 and the negative electrode plate cassette
31 are processed into predetermined constitutions respectively by a separator
processing mechanism
77 shown in FIG. 4A to FIG. 4C, and a negative electrode
plate processing mechanism
59 shown in FIG. 3 as described later, they are
supplied for the group winding head unit
20 as shown by arrows in the drawing.
After the separator mount jig
28 and the negative electrode plate mount
jig
32 have supplied the separator
7 and the negative electrode plate
4 respectively for the group winding head unit
20, the empty separator,mount
jig
28 and negative electrode plate mount jig
32 are detached from
the group winding head unit
20 when they are transported to predetermined
positions as the work table
19 rotates, and then they are transported to
return to the processing mechanisms
77 and
59 respectively. This
procedure is detailed later. The spiral electrode group (not shown) constituted
by winding the separator
7, the positive electrode plate
8, and the
negative electrode plate
4 is taken out while the spiral electrode group
is stored in a transportation container
38 circularly transported along
a transportation conveyer
37, and then is transported to a next process.
FIG. 2A to FIG. 2C are perspective views respectively showing the separator
mount jig
28, the negative electrode plate mount jig
32, and the
positive electrode plate mount jig
29. First, the separator mount jig
28
in FIG. 2A has such a constitution that a pair of winding shafts
41A and
41B including an engagement slit
40 along the shaft center are provided
in parallel with each other, the individual top ends of the winding shafts
41A
and
41B are supported rotatably by a main unit
39, and a holder recess
42 in a groove shape extending in the shaft direction (in the up/down direction
in the drawing) is provided at the center of the main unit
39.
The pair of winding shafts
41A and
41B are rotatably supported
respectively by bearings (not shown) in the main unit
39. However, a braking
force is applied such that the separator
7 wound on the winding shafts
41A
and
41B so as to be mounted between them is maintained without generating
slack, elongation, and crease as long as a force is not applied to the separator
7.
Also, connection shafts
43 with a diameter
