US 5,499,234 A · Method for recharging flooded cell batteries

Abstract

Maintenance free flooded electrolyte battery cycle life is extended by controlling charge acceptance and gassing during recharge. Charge acceptance is improved by periodically discharging the battery during a portion of the recharge which removes surface charge and reduces overall cell voltage. Gassing is purposefully introduced during periodic supply currents which are interspersed with the periodic discharges of the battery. The supply currents both restore energy to the battery and agitate the electrolyte sufficient to destratify same thereby reducing plate damage and charge gradients thereon. The method results in shorter charge times, full capacity recharges and extended cycle life resulting therefrom and from reductions in corrosive interactions of the electrolyte with the battery plates.

Claims5

Dependent claims

A method of improving cycle life of maintenance free flooded cell water-diluted electrolyte batteries comprising the steps of:

(a) during a bulk charge cycle,
charging the battery to substantially full capacity;
(b) during a charge restoral portion of a pulse charge/discharge cycle,
repetitively supplying a supply current to the battery for a supply duration at intervals interspersed with discharging a discharge current from the battery for a discharge duration, said supply current being apportioned between a gassing current effective to electrolyze water thereby evolving gas and a charge current effective to convert battery plate material thereby restoring charge, said supply duration apportioned between a charge duration wherein charge restoral dominates gas evolution and a gassing duration wherein gas evolution dominates charge restoral;
and,
controlling a combination of said supply current and said supply duration to contemporaneously yield a high charge restoral rate and a destratifying gas evolution rate.

3 more elements

Dependencies are inferred from the claim text.

Method for recharging flooded cell batteries

Life of this patent

Method for recharging flooded cell batteries

Life of this patent

Abstract

Claims5