CN215119174U

CN215119174U - Lithium ion battery PTC tab capable of improving safety performance

Info

Publication number: CN215119174U
Application number: CN202120155545.5U
Authority: CN
Inventors: 林俊颇; 林俊仰; 黎显龙; 梁宏发; 杨联贵
Original assignee: Zhongshan Tianmao Battery Co Ltd
Current assignee: Zhongshan Tianmao Battery Co Ltd
Priority date: 2021-01-20
Filing date: 2021-01-20
Publication date: 2021-12-10
Anticipated expiration: 2031-01-20

Abstract

The utility model relates to a PTC tab of lithium ion battery for improving safety performance, which comprises a tab, wherein the tab is a PTC tab, one end of the PTC tab is electrically connected with a first pure nickel piece, and the other end of the first pure nickel piece is electrically connected with a battery cover plate; the other end of the PTC tab is electrically connected with one end of the pure nickel sheet II, and the other end of the pure nickel sheet II is electrically connected with the hollow foil in the middle of the total length of the battery cell pole piece. The utility model discloses because replace traditional pure nickel and copper-nickel with PTC and act as utmost point ear, promote the security performance of electric core by a wide margin: under the condition of overcurrent charging, the effect of limiting current is achieved, and other materials in the battery cell are prevented from being damaged, so that the safety performance of the battery cell is effectively improved. On the other hand, the PTC tabs are welded on the pole piece position which is half of the designed fold number, so that the internal resistance of the battery cell can be reduced, the energy consumption is reduced, and the electrical performance of the battery cell is ensured to be normal.

Description

Lithium ion battery PTC tab capable of improving safety performance

Technical Field

The utility model relates to a lithium ion battery especially relates to a lithium ion battery's PTC utmost point ear of improvement security performance.

Background

The PTC tab is the tab of the lithium ion battery cell pole piece made of PTC material. A PTC material is a semiconductor material typically having temperature sensitivity, and its resistance value increases stepwise with an increase in temperature above a certain temperature (curie temperature). At present, the certification requirement of a lithium ion battery PSE reaches the high-strength overcharge level of 1C10V, the test standard is that the battery can not be ignited and exploded, but the cathode lug in the same type of product only uses a pure nickel or copper-nickel lug, the safety performance hardly reaches the overcharge requirement of the high standard, because when the two lugs are subjected to large-current overcharge, the two lugs can not generate effective protection, then a large amount of heat energy is generated, the internal material of the battery core is damaged, and the battery core is caused to ignite and explode. On the other hand, if the tab is welded at one end of the pole piece according to the conventional method, the internal resistance of the battery cell can be greatly increased, the loss can also be very large, and the electrical performance of the battery cell is influenced.

Disclosure of Invention

The utility model aims at providing an improve security performance's lithium ion battery's PTC utmost point ear to above-mentioned problem exactly.

The utility model adopts the technical proposal that: the PTC tab of the lithium ion battery with improved safety performance comprises a tab, wherein the tab is a PTC tab, the width of the PTC tab is the same as that of a battery cell tab, one end of the PTC tab is electrically connected with a first pure nickel piece, and the other end of the first pure nickel piece is electrically connected with a battery cover plate; the other end of the PTC tab is electrically connected with one end of the pure nickel sheet II, and the other end of the pure nickel sheet II is electrically connected with the hollow foil in the middle of the total length of the battery cell pole piece.

The PTC tabs are made of temperature sensitive semiconductor materials.

And 5-15 mm wide hollow foils are reserved on the pole pieces connected with the tabs and used as the welding positions of the PTC tabs.

And a high-temperature-resistant adhesive tape is pasted at the joint of the PTC tab and the pure nickel sheet and the cover plate.

The utility model has the advantages that: because be equipped with PTC utmost point ear, PTC replaces traditional pure nickel and copper-nickel to act as utmost point ear, promotes the security performance of electric core by a wide margin: under the condition of overcurrent charging, the temperature rise can be caused by the violent reaction inside the battery cell, then the resistance value of the PTC can be increased due to the rise of the temperature, the effect of limiting the current is achieved, and other materials inside the battery cell are prevented from being damaged, so that the safety performance of the battery cell is effectively improved. On the other hand, the welding position of the tab is as follows: the PTC tab is welded on the pole piece position which is half of the designed fold number, namely the middle position of the whole length of the pole piece, so that the internal resistance of the battery cell can be reduced, the energy consumption is reduced, and the electrical performance of the battery cell is ensured to be normal.

Drawings

Fig. 1 is a schematic diagram of one embodiment of the present invention.

Fig. 2 is the utility model discloses the schematic diagram of being connected with the pole piece of electric core.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

As shown in fig. 1 and fig. 2, the utility model discloses a tab, tab be PTC utmost point ear 2, PTC utmost point ear's width is the same with electric core utmost point ear, certainly the size also can be close or be greater than the size of conventional utmost point ear. One end of the PTC tab is electrically connected with the first pure nickel sheet 21, and the other end of the first pure nickel sheet is electrically connected with the battery cover plate; the other end of the PTC tab is electrically connected with one end of the second pure nickel sheet 22, and the other end of the second pure nickel sheet is electrically connected with the hollow foil 11 in the middle of the total length of the cell pole piece 1. The pure nickel sheet is arranged, so that the traditional equipment can be conveniently welded with the pole piece and the cover plate. The utility model discloses a PTC utmost point ear is temperature sensitivity semiconductor material. And 5-15 mm wide empty foil is reserved on the pole piece connected with the pole lug and used as a position for welding the PTC pole lug. The "empty foil" exposes the metallic portion of the substrate. The joint of the PTC tab and the pure nickel sheet and the cover plate is pasted with a high temperature resistant adhesive tape. The tab of this embodiment is manufactured: selecting PTC which meets the requirements of the battery, connecting pure nickel with the length of 8mm on two ends by using glue, using the pure nickel as a medium for welding the PTC on the copper foil of the pole piece, and then sticking high-temperature-resistant glue on one end of the connecting cover plate and the PTC. Welding positions: when the length position of the pole piece reaches half during coating, 10mm of empty foil is reserved as a position for welding the PTC pole lug. The welding process uses the traditional welding method, namely nickel is welded on the copper foil of the pole piece, and the traditional equipment is used. Under normal conditions, because of the centered welding of the lugs, the resistance value of the battery cell is reduced, so the loss is also very small, and the normal work of the circuit is not influenced; if overcurrent happens, the temperature of the battery core rises, the resistance value of the battery core rises sharply, the effect of limiting current is achieved, other materials in the battery core are prevented from being damaged, and therefore the safety performance of the battery core is effectively improved.

In the description of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the term "connected" is to be understood in a broad sense, for example, it may be a fixed connection, a glue or tape connection, a mechanical connection, or an electrical connection; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Claims

1. The utility model provides an improve lithium ion battery's PTC utmost point ear of security performance, includes utmost point ear, its characterized in that: the electrode lug is a PTC electrode lug (2), the width of the PTC electrode lug is the same as that of the battery core electrode lug, one end of the PTC electrode lug is electrically connected with a first pure nickel sheet (21), and the other end of the first pure nickel sheet is electrically connected with the battery cover plate; the other end of the PTC tab is electrically connected with one end of a pure nickel sheet II (22), and the other end of the pure nickel sheet II is electrically connected with the hollow foil in the middle of the total length of the battery cell pole piece.

2. The PTC tab of a lithium ion battery for improving safety performance according to claim 1, wherein: the PTC tabs are made of temperature sensitive semiconductor materials.

3. The PTC tab of a lithium ion battery for improving safety performance according to claim 1, wherein: and 5-15 mm wide hollow foils are reserved at the pole pieces connected with the tabs and used as the welding positions of the PTC tabs.

4. The PTC tab of a lithium ion battery for improving safety performance according to claim 1, wherein: and a high-temperature-resistant adhesive tape is pasted at the joint of the PTC tab and the pure nickel sheet and the cover plate.