adsorbed on the diaphragm surface or the top of the single-cell battery shell, the bottom of the dust. Manufacturing environment, process control bad circumstances, will form a large number of positive/negative pole piece of dust and welding caused by metal dust, and electrostatic adsorption on the diaphragm surface. Pole piece itself is not smooth, powder bonding strength is not enough, itself will cause this problem.
The positive/negative electrode sheet formed when winding / laminating is misaligned.
Metal solder joints, pole piece edge burr.
Lithium dendrite is formed on both sides of the separator, and lithium dendrite is formed due to local electrochemical reaction or overcharge caused by inhomogeneous reaction.
Uneven distribution of the electrolyte results in inconsistent utilization of positive / negative pole pieces.
The material itself. Material purity is not high, and the electrolyte compatibility is not good, the cathode metal material is not high voltage, the negative metal materials and lithium alloy, may form impurity deposition or lithium dendrites.
External factors. The external mechanical force causes the deformation of the single-cell shell and then cause the diaphragm displacement and breakage. Excessively high ambient temperature leads to over-shrinkage, breakage, overcharge and forced discharge of the separator, resulting in the formation of lithium dendrite inside the cell may cause Internal short circuit.