What does the lithium battery manufacturer tell you about the reason for the malfunction of the lithium battery?
1. Reason for low capacity failure of lithium batteries: insufficient amount of attached materials; There is a significant difference in the amount of material attached to both sides of the polarizer; Pole fracture; Low electrolyte; Low electrolyte conductivity; The positive and negative electrode plates are not properly matched; The porosity of the membrane is small; Adhesive aging → detachment of attached materials; The core is too thick and not fully charged during capacity division; The positive and negative electrode materials have a smaller specific capacity.
2. Reason for high internal resistance fault of lithium battery: virtual welding between negative electrode and electrode lug; Positive electrode plate and electrode ear have virtual welding; Positive electrode ear and cap have virtual welding; Negative electrode ear and shell virtual welding; The contact resistance between rivets and pressure plates is high; Positive electrode without conductive agent added; The electrolyte does not contain lithium salts; The battery has experienced a short circuit in the past; The porosity of the diaphragm paper is small.
3. Reasons for low voltage fault in lithium batteries: side reactions (electrolyte decomposition; impurities in the positive electrode; presence of water); Not fully formed (S film not yet formed safely); Customer's circuit board leakage (referring to the batteries returned by the customer after processing) The customer did not perform spot welding as required (on the battery cells processed by the customer); skin needling; Micro short circuit; The negative electrode produces dendrites.
4. Reason for excessive thickness fault: leakage of weld seam; Electrolyte decomposition; Undried moisture; Poor sealing of the cap; The shell wall is too thick; The shell is too thick; The core is too thick (too much attached material; the pole piece is not compacted; the diaphragm is too thick).
5. Reasons for abnormal lithium battery formation: incomplete formation (incomplete and dense S film); Excessive baking temperature → adhesive aging → material detachment; Low specific capacity of negative electrode; Lithium batteries have more positive electrode materials and less negative electrode materials; Cap leakage, weld leakage; The electrolyte decomposes and the conductivity decreases.
6. Reason for lithium battery explosion: there is a malfunction in the distribution cabinet (causing overcharging); Poor diaphragm closure effect; Internal short circuit.
What are the common faults of lithium batteries?
● Internal resistance of battery
The negative and positive electrode plates of lithium batteries are not welded properly during welding, or the internal resistance between rivets and pressure plates is too high, which can affect the internal resistance of lithium batteries. The small pores of the separator can also affect the internal resistance of the battery.
● Battery voltage
In the production process of
lithium batteries, impurities are mixed into the positive electrode and dendrites are generated in the negative electrode, which can cause a decrease in the voltage of the lithium battery. Incomplete formation of SEI film during the formation process can also lead to low voltage in lithium batteries.
● Abnormal temperature
If the temperature of a lithium battery is abnormal during charging or discharging, such as being too high. The reason for this situation may be a slight short circuit inside the lithium battery.
Summary: The above are common faults and some reasons for lithium batteries. As lithium batteries may cause faults, you can pay more attention to them. We also need to operate lithium batteries correctly to avoid accidents.
