Why are cells appear bulge deformation phenomenon?

Batteries in bulge deformation, mainly by the body brush pressure shock, as a result of the increasing main reason has the following points.
(1) relief valve open valve pressure is too high, or the relief valve block. When the pressure increases to a certain degree of the valve body can’t normal open, in this case is bound to cause bulge deformation.
(2) set too high float charging voltage, charging current is large, lead to positive plate on O2 precipitation is accelerated, and too late in the cathode compound, at the same time, the temperature rise of cells in the body quickly, the exhaust less, when the pressure reaches a certain, the bulge deformation of VRLA battery.
(3) in the operation of VRLA batteries in series battery pack, in particular, if the battery charging, if there is poor quality batteries often appear internal gas composite adverse phenomenon, which appear beat phenomenon.
(4) for VRLA batteries belong to the poor fluid type design, in combination with reserved way, and if there is a “rich liquid” phenomenon, can block the O2 diffusion to the cathode, reduce the recombination rate of O2, the pressure in the body.