A short circuit in a lithium iron phosphate battery occurs when the positive and negative terminals are connected in a straight line, creating an abnormal circuit. This can lead to severe damage to the battery, combustion, and potentially a fire, or the battery container may explode due to excessive pressure. The short circuit in a lithium iron phosphate battery is caused by contact between the positive and negative terminals, and its causes are complex.
① Manufacturing process
The electrode surface has burrs that puncture the diaphragm and cause a short circuit between the positive and negative electrodes, or this could be due to improper manufacturing processes.
② Usage process
Overheating in lithium-ion batteries can cause short circuits due to the melting of the separator. Micro-short circuits are primarily caused by burrs on the battery plates and can sometimes be eliminated by high-current discharge. Micro-short circuits result in insufficient voltage. During use, lithium metal batteries are prone to micro-short circuits due to the formation of dendritic crystals from the crystallization of lithium metal, which can lead to large short circuits in severe cases. Low temperatures also easily cause micro-short circuits in lithium-ion batteries.
③ Poor diaphragm quality
The lithium battery cell separator is of substandard quality, and lithium-ion battery packs are often charged and discharged at high currents during use. The separator cannot withstand the huge flow of lithium ions passing through it in a short period of time, resulting in local or large-area damage, which directly causes the battery cell to overheat and become damaged.
④ Leakage
When the internal temperature of a lithium iron phosphate battery rises slowly, the outer casing gradually melts, rendering the protective layer ineffective and leading to leakage of the corrosive electrolyte. This can then cause a short circuit in the battery.
