(1) Electrolyte level was too low (2) Short circuit between pole plates (3) Sulfonation of pole plate (4) Poor wire contact, large amount of oxides, lack of charge
(1) Add distilled water or dilute sulfuric acid with a density of 1.28g/cm3 (g/cm3) (2) Remove deposits, replace electrolyte. (3) Charge and discharge the battery repeatedly, eliminate vulcanization (4) Tighten the connection, remove oxides, lubricate the terminals with a thin layer of Vaseline