Battery pack and method for manufacturing battery pack
A battery pack includes a stack of a plurality of battery cells each including positive and negative electrode lead tabs led out of a laminate film casing, and a coupling assisting member. The coupling assisting member includes a conductive plate member fixing portion that fixes a conductive plate member having first and second main surfaces in a front-to-back relationship. Either one of the positive and negative lead tabs of one battery cell is conductively connected to the first main surface of the conductive plate member. A lead tab of a battery cell adjoining the one battery cell, having a polarity different from that of the lead tab of the one battery cell, is inserted through the second slit portion and conductively connected to the second main surface of the conductive plate member. Vibration transmission ratio changing bends are provided on the lead tabs.
1. A battery pack comprising:
a plurality of battery cells stacked together, each of the plurality of battery cells including a lead tab led out of a laminate film casing,
a coupling assisting member that is configured to assist in electrically connecting adjoining battery cells of the plurality of battery cells, the coupling assisting member including slit portions and a plurality of guiding plates, each of the plurality of guiding plates corresponding to a lead tab of the plurality of battery cells,
and
a plurality of conductive plate members each having a main surface disposed between and electrically and conductively connected to lead out tabs of two adjacent battery cells of the plurality of battery cells; wherein
the plurality of the guiding plates are provided in pairs with respective ones of the plurality of conductive plate members interposed therebetween,
each of the lead out tabs of the plurality of battery cells is shaped to include a bend disposed adjacent to the battery main body, the bend being configured to change a vibration transmission ratio, and
the lead tabs of the plurality of battery cells pass through and between the slit portions, and end portions of the lead tabs extend along the main surface of the conductive plate members.
2. A method for manufacturing a battery pack including a stack of a plurality of battery cells that each include a lead tab led out of a laminate film casing, a coupling assisting member which includes slit portions, and that assists in electrically connecting adjoining battery cells of the plurality of battery cells, the method comprising:
fixing a plurality of conductive plate members, each of which being included in the coupling assisting member and each having a main surface, to two adjacent battery cells of the plurality of battery cells, such that the main surface of each of the plurality of conductive plate members is disposed between and electrically and conductively connected to the lead out tabs of the two adjacent battery cells of the plurality of battery cells;
providing a bend in each of the lead out tabs, the bend being configured to change a vibration transmission ratio by making contact between each lead tab of the plurality of battery cells and respective ones of a plurality of guiding plates of the coupling assisting member, each of the plurality of guiding plates corresponding to a lead tab of the plurality of battery cells,
wherein the plurality of the guiding plates are provided in pairs with respective ones of the plurality of conductive plate members interposed therebetween,
each ones of the pairs of the plurality of the guiding plates have an angled surface that contacts respective ones of the lead tabs of the plurality of battery cells, the angled surface being angled with respect to the respective conductive plate members such that the plurality of the guiding plates form a curved vibration transmission ratio changing bend in each of the lead out tabs of the plurality of battery cells, and
wherein the lead tabs of the plurality of battery cells pass through and between the slit portions, and end portions of the lead tabs extend along the main surface of the conductive plate members.
3. The battery pack according to claim 1 , wherein the coupling assisting member includes a fixing portion that fixes the plurality of conductive plate members.
4. The method for manufacturing a battery pack according to claim 2 , wherein the coupling assisting member includes a fixing portion that fixes the plurality of conductive plate members.
5. The battery pack according to claim 1 , wherein the battery pack has a natural frequency f n , such that a frequency ratio u, which is a ratio of the natural frequency f n of the battery pack to a frequency f of a device which connects each of the plurality of the lead tabs of the plurality of battery cells and respective ones of the plurality of the main surfaces of the plurality of the conductive plate members is greater than √2.
6. The method for manufacturing the battery pack according to claim 2 , the method further comprising adjusting the bend such that a frequency ratio u, which is a ratio of a natural frequency fn of the battery pack to a frequency f of a device which connects each of the plurality of the lead tabs of the plurality of battery cells and respective ones of the plurality of the main surfaces of the plurality of the conductive plate members is greater than √2.
7. The battery pack according to claim 1 , further comprising a reinforcing member configured to be engaged with the coupling assisting member, wherein the reinforcing member is disposed parallel to the plurality of battery cells.
8. The method for manufacturing a battery pack according to claim 2 , the battery packing further comprising a reinforcing member configured to be engaged with the coupling assisting member, and wherein the reinforcing member is disposed parallel to the plurality of battery cells.