Lithium Battery Tabs

Jan 04,2024

1.Lithium battery tab material

Lithium-ion battery tabs, as shown in the figure below, are metal conductors that lead the positive and negative electrodes out of the battery cells. The complete tabs are mainly composed of insulating sealant and metal conductive matrix. For lithium-ion batteries, the positive electrode uses aluminum tabs, and the negative electrode uses pure nickel tabs or nickel-plated copper tabs.

2. Lithium battery tab structure

The internal structure of consumer lithium-ion batteries is mainly divided into four types according to their production methods: normal structure, tab-centered structure, multi-tab structure, and laminated structure. The normal structure of the positive and negative electrodes has only one tab, which is located at one end of the pole piece and is made by winding; the tab in the middle structure is located in the middle of the batteryelectrode, usually through laser cleaning, spacer coating, tape application, etc. The internal resistance of the battery is smaller and the rate performance is better; the multi-tab woundelectrodehas multiple tabs, and the tab positions are different according to the design. The battery resistance is smaller and the rate performance of the battery is better; stacked The sheet battery is made by cutting theelectrodeinto a specific shape and alternately folding the positive and negative electrodes. There is a tab in each layer. The battery with this structure has the best rate performance. Battery Tab

2.1Tab-centered structure

The position of the tabs has a significant impact on the internal resistance and rate of the lithium-ion battery. When the tabs are in the middle of the positive and negative electrodes, the battery has the best internal resistance and rate performance, and its performance is close to that of batteries with lamination technology. The picture below shows a comparison between the pole-tab center-mounted structure and the normal structure. The pole-tab of the normal structure is located at one end of the pole piece, while the pole-tab-centered structure has the pole tab located in the middle of the battery pole piece.

2.2 Multi-tab winding structure

Thepicture below shows the multi-pole winding structure. The multi-tab winding

technology cuts a fixed tab shape into the carrier. After the winding is completed, the carrier is welded and the tabs are drawn out to form a multi-tab battery.

Multi-taab winding has more tabs and is more evenly distributed. This structure has better battery rate performance and smaller charge and discharge temperature rise. It is suitable for high-power equipment. Currently, many drones use this structure. Due to its welding requirements and higher precision, batteries made with this structure are more expensive. The advantages of the multi-tab structure are: further reducing the battery impedance, improving the battery's high-rate charge and discharge performance, and supporting 5C~10C discharge; effectively reducing the temperature rise of the battery under high-rate discharge, and the surface temperature rise of the battery under 10C discharge is lower than 20°C; Low temperature significantly increases battery cycle life.

2.3 Laminated structure

Comparedwith multi-tab winding, each layer of the laminated battery leads to a tab. The

fast charging performance of the battery made with this structure is the highest among various structures at present. However, due to the limitation of its degree of automation, it is currently less used in the field of consumer electronics and is mainly used in military industry, power batteries and other fields. It is believed that with the improvement of automation capabilities, lamination technology will become mainstream in the future. The figure below is a schematic diagram of a stacked structure battery.