Common faults and causes of lithium batteries are as follows:
1. Low battery capacity
Causes: The amount of attached material is small; the amount of attached material on both sides of the pole piece is quite different; the electrolyte is small; the electrolyte conductivity is low; the diaphragm porosity is small; the core is too thick (not dried or the electrolyte is not penetrated). When it is not fully charged; the specific capacity of the positive and negative materials is small.
2. High battery internal resistance
Causes: virtual welding of the negative electrode sheet and the tab; virtual welding of the positive electrode sheet and the tab; virtual welding of the positive electrode tab and the cap; virtual welding of the negative electrode tab and the shell; large internal resistance between the rivet and the pressure plate; no conductive agent is added to the positive electrode; no electrolyte Lithium salt; the battery has been short-circuited; the porosity of the diaphragm paper is small.
3. Low battery voltage
Side reactions (decomposition of electrolyte; impurities in the positive electrode; water); leakage of the customer's circuit board (referring to the battery sent back after the customer processing); the customer fails to spot welding (the battery after the customer processing); burr; micro Short circuit; dendrites are generated on the negative electrode.
4. The reasons for the failure of super thick are as follows:
Weld leakage; electrolyte decomposition; unseasoned moisture; poor sealing of cap; too thick shell wall; too thick shell; too thick core (too much material attached; not compacted pole piece; too thick diaphragm).
5. Abnormal battery formation
Not formed well (SEI film is incomplete and dense); baking temperature is too high → binder aging → stripping; negative electrode specific capacity is low; there are more positive electrode materials and less negative electrode materials; cap leaks, weld leaks; The electrolyte decomposes and the conductivity decreases.
6. The battery explodes
The sub-container is faulty (causing overcharge); the diaphragm closing effect is poor; internal short circuit.
7. Battery short circuit
Material dust; the casing is broken; the ruler is scraped (the diaphragm paper is too small or not properly padded); the winding is not uniform; not wrapped; the diaphragm has a hole;
8. The battery is disconnected.
The tabs and rivets are not welded well, or the effective welding area is small;
The connecting piece is broken (the connecting piece is too short or the welding is too low when spot welding with the pole piece)
