Pole piece structure of single-lug centrally-mounted lithium battery
By placing tabs in the lithium battery electrode sheet and combining them with a high-temperature adhesive tape misalignment design, the problems of low energy density, poor safety, and high manufacturing difficulty caused by traditional tab designs are solved, thus achieving the manufacturing of lithium batteries with high energy density, strong safety, and low cost.
Patent Information
- Application Number
- CN202520443928.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-03-14
AI Technical Summary
Traditional tab designs occupy an effective area, resulting in low battery energy density, poor safety, high manufacturing difficulty and cost, and are prone to temperature rise and short circuit during high current discharge.
The battery adopts a single-tab centrally located lithium battery electrode structure, with the tab placed in the middle of the electrode. Combined with the staggered distribution of high-temperature adhesive tape, it reduces the waste of effective area, increases the buffer zone, optimizes the current distribution, and uses highly conductive and high-temperature resistant materials.
It improves battery energy density and cycle performance, reduces manufacturing difficulty and cost, extends battery life, enhances safety, reduces short-circuit risk, and facilitates automated production.
Smart Images
Figure CN223956571U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of lithium ion battery, in particular to a single pole lug middle type lithium battery pole piece structure. BACKGROUND
[0002] The core component of lithium ion battery is positive and negative pole piece, and the pole lug as the electrode lead-out part plays a key role in the process of battery assembly and connection. The traditional pole lug design mostly adopts side or edge type layout, and its characteristics and defects are mainly as follows: the pole lug position is close to the edge of the battery, and part of the effective area is occupied; under the condition of large current discharge or overcharge / overdischarge, local temperature rise is easily caused, and even short circuit is caused; the safety performance is limited, and it is difficult to meet the demand of high energy density battery; the existing high-power battery uses the laminated technology to increase the number and structure layout of the pole lug, and the process is complex, and the production efficiency is low.
[0003] The existing pole lug design often sacrifices the safety and cycle life of the battery when improving the energy density. In addition, the unreasonable layout of the pole lug position also increases the manufacturing difficulty and cost. INVENTION CONTENTS
[0004] The utility model aims at the problems in the background art, and provides a single pole lug middle type lithium battery pole piece structure, the pole lug is distributed in the middle, the energy density, cycle performance and safety of the battery are improved, and the manufacturing difficulty and cost are reduced.
[0005] The technical scheme of the utility model relates to a single pole lug middle type lithium battery pole piece structure, which comprises an aluminum foil, a coating area and a pole lug. Two sides of the aluminum foil in the thickness direction are respectively an A surface and a B surface. The coating area comprises an A surface coating area extending from both ends of the A surface of the aluminum foil to the middle and a B surface coating area extending from both ends of the B surface of the aluminum foil to the middle. An A surface non-coating empty foil area is left in the middle of the A surface of the aluminum foil, and a B surface non-coating empty foil area is left in the middle of the B surface of the aluminum foil. High-temperature adhesive paper is attached to both ends of the A surface non-coating empty foil area and both ends of the B surface non-coating empty foil area. One end of the A surface non-coating empty foil area is aligned with the B surface non-coating empty foil area, and the other end of the A surface non-coating empty foil area is distributed in a staggered manner with the other end of the B surface non-coating empty foil area. The pole lug is welded in the middle of the aluminum foil.
[0006] Preferably, the length of the A surface non-coating empty foil area is greater than the length of the B surface non-coating empty foil area.
[0007] Preferably, the high-temperature adhesive paper at both ends of the A surface non-coating empty foil area is respectively first high-temperature adhesive paper and third high-temperature adhesive paper, and the high-temperature adhesive paper at both ends of the B surface non-coating empty foil area is respectively second high-temperature adhesive paper and fourth high-temperature adhesive paper.
[0008] Preferably, the A surface of the aluminum foil has an A surface pole lug position, the B surface has a B surface pole lug position, and the pole lug is located at the A surface pole lug position and the B surface pole lug position.
[0009] Preferably, the first high-temperature adhesive tape is located at the tab position on side A, and the second high-temperature adhesive tape is located at the tab position on side B.
[0010] Compared with the prior art, the present invention has the following beneficial technical effects:
[0011] The centrally located tabs in this invention reduce wasted effective area, lower temperature rise at the tabs, extend battery life, and improve battery energy density, cycle performance, and safety. They also reduce manufacturing difficulty and cost, facilitate automated production, and improve manufacturing efficiency. The staggered distribution of the uncoated foil areas on side A and side B increases the buffer zone between the tabs and the active material. During the winding and wrapping of the battery electrodes, this effectively isolates the contact between the coated negative electrode area and the uncoated positive electrode area, increasing the structural safety of the battery electrodes, improving battery safety performance, and reducing the risk of short circuits and failures. Attached Figure Description
[0012] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model.
[0013] Reference numerals: 1. Aluminum foil; 2. Coated area on side A; 21. Uncoated foil area on side A; 3. Coated area on side B; 31. Uncoated foil area on side B; 4. Tab on side A; 5. Tab on side B; 61. First high-temperature adhesive tape; 62. Second high-temperature adhesive tape; 63. Third high-temperature adhesive tape; 64. Fourth high-temperature adhesive tape. Detailed Implementation
[0014] like Figure 1 As shown in the figure, the single-tab centrally located lithium battery electrode structure proposed in this embodiment includes an aluminum foil 1, a coating area, and a tab.
[0015] The aluminum foil 1 has two sides, A and B, along its thickness. Side A has tab 4, and side B has tab 5. The tabs are welded to the center of the aluminum foil 1, specifically at tab 4 on side A and tab 5 on side B. Positioning the positive and negative tabs in the central area of the electrode sheet, away from the effective area of the active material, maximizes the utilization of the active material. This central tab design facilitates automated battery assembly and improves production efficiency. Furthermore, using highly conductive and high-temperature resistant materials (such as nickel-copper composites) in the tab area reduces the likelihood of breakage or failure at high temperatures and enhances the conductivity of the tabs, reducing resistance when current flows through them.
[0016] The coating area includes coating area 2 on side A, extending from both ends of side A of aluminum foil 1 towards the middle, and coating area 3 on side B, extending from both ends of side B of aluminum foil 1 towards the middle. An uncoated empty foil area 21 is left in the middle of side A of aluminum foil 1, and an uncoated empty foil area 31 is left in the middle of side B of aluminum foil 1. High-temperature adhesive tape is applied to both ends of both sides of uncoated empty foil area 21 on side A and uncoated empty foil area 31 on side B. This means that a layer of high-temperature adhesive tape is applied to the misaligned coating areas of uncoated empty foil areas 21 on side A and 31 on side B, effectively preventing lithium plating in the battery due to misalignment of the positive and negative electrode coating areas caused by equipment, personnel operation, or other factors during mass production.
[0017] Regarding the distribution of the uncoated empty foil area 21 on side A and the uncoated empty foil area 31 on side B, one end of the uncoated empty foil area 21 on side A is aligned with the uncoated empty foil area 31 on side B. Therefore, the coated areas 2 on side A and 3 on side B are also aligned at this point, and the electrode tabs are welded to the aluminum foil at this location. The other end of the uncoated empty foil area 21 on side A is offset from the other end of the uncoated empty foil area 31 on side B, and the length of the uncoated empty foil area 21 on side A is greater than the length of the uncoated empty foil area 31 on side B.
[0018] The high-temperature adhesive tapes at both ends of the uncoated foil area 21 on side A are the first high-temperature adhesive tape 61 and the third high-temperature adhesive tape 63, respectively. The high-temperature adhesive tapes at both ends of the uncoated foil area 31 on side B are the second high-temperature adhesive tape 62 and the fourth high-temperature adhesive tape 64, respectively. Among them, the first high-temperature adhesive tape 61 is located at the tab position 4 on side A, and the second high-temperature adhesive tape 62 is located at the tab position 5 on side B.
[0019] The centrally located tabs in this embodiment reduce wasted effective area, improve battery energy density, cycle performance, and safety, and reduce manufacturing difficulty and cost. Tab positions 4 on side A and 5 on side B are located in the middle of the coating area of a single electrode sheet, shortening the battery's charge / discharge current path, maximizing the utilization of active material, effectively increasing high-current charge / discharge, reducing impedance, and improving the battery's median voltage and rate performance. The staggered distribution of the uncoated foil areas 21 on side A and 31 on side B increases the buffer zone between the tabs and the active material. During battery electrode winding and wrapping, this effectively isolates the contact between the negative electrode coating area and the positive electrode uncoated area, increasing the safety of the battery electrode structure, improving battery safety performance, and reducing the risk of short circuits and failures.
[0020] Furthermore, the current distribution has been optimized, reducing temperature rise at the tabs, extending battery life, facilitating automated production, and improving manufacturing efficiency. This electrode structure can be widely used in the manufacture of high-energy-density lithium-ion batteries, and is particularly suitable for fields such as power tools and drones.
[0021] The embodiment of the utility model is described in detail above in combination with the drawings, but the utility model is not limited to this, and various changes can be made within the knowledge range possessed by the person skilled in the art without departing from the purpose of the utility model.
Claims
1. A single-pole tab-in-the-middle lithium battery electrode sheet structure, characterized by, Comprise: Aluminum foil (1), the thickness direction two sides are A side and B side respectively; Coating area, including A side coating area (2) extending from both ends of A side of aluminum foil (1) to the middle and B side coating area (3) extending from both ends of B side of aluminum foil (1) to the middle, leaving A side uncoated empty foil area (21) in the middle of A side of aluminum foil (1), leaving B side uncoated empty foil area (31) in the middle of B side of aluminum foil (1), the both ends of A side uncoated empty foil area (21) and the both ends of B side uncoated empty foil area (31) are pasted with high temperature adhesive paper, the one end of A side uncoated empty foil area (21) is aligned with B side uncoated empty foil area (31), the other end of A side uncoated empty foil area (21) is distributed staggered with the other end of B side uncoated empty foil area (31); Tab, welded in the middle of aluminum foil (1).
2. The lithium battery pole piece structure of the single-pole ear middle placement type according to claim 1, characterized in that, The length of A side uncoated empty foil area (21) is greater than the length of B side uncoated empty foil area (31).
3. The lithium battery pole piece structure of the single-pole ear middle placement type according to claim 1, characterized in that, The high temperature adhesive paper of both ends of A side uncoated empty foil area (21) is first high temperature adhesive paper (61) and third high temperature adhesive paper (63) respectively, the high temperature adhesive paper of both ends of B side uncoated empty foil area (31) is second high temperature adhesive paper (62) and fourth high temperature adhesive paper (64) respectively.
4. The lithium battery pole piece structure of the single-pole ear middle placement type according to claim 3, characterized in that, A side of aluminum foil (1) has A side tab position (4), B side has B side tab position (5), tab is located at A side tab position (4) and B side tab position (5).
5. The lithium battery pole piece structure of claim 4, wherein the lithium battery pole piece structure is a single-pole-ear-in-the-middle structure. First high temperature adhesive paper (61) is located at A side tab position (4), second high temperature adhesive paper (62) is located at B side tab position (5).