4. When Must a Battery Be Opened?
(a) When prolonged charging (72 hours or more) will not cause gravity or voltage to rise. Such trouble is due to defective plates and separators.
(b) When battery case is badly acid soaked. A slightly acid soaked case need not be discarded, but if the damage caused by the acid has been excessive, a new case is needed. Plates may also be damaged.
(c) When one or more jars are cracked. New jars are needed. The plates may also be damaged.
(d) When one or more cells are "dead," as indicated by little or no voltage, even on open circuit. New plates (positives at least) may be required.
(e) When battery is more than a year old and action is unsatisfactory. (Battery will not hold its charge.) Battery may have to be junked, or new separators may be required. Every battery should be reinsulated at least once during its lifetime.
(f) When a blacksmith, tinsmith, or plumber have tried to repair a case, Fig. 189.
Fig. 189. A Blacksmith and Tinsmith Tried Their Hands on This Case, Lower Part Enclosed in Tin, Strap Iron, Covered with Friction Tape, Around The Top.
(g) When the ends of case are bulged. A new case is needed. If the battery has been frozen it should generally be junked. There are some cases on record of a frozen battery having been thawed out and put in serviceable condition by a long charge at a low rate followed by several cycles of discharge and recharge. Generally, at least, a new case, jars, and positives are required.