PURPOSE: To reduce the self-discharge of a sealed lead-acid battery during a shelf period, and improve the capacity recoverability thereof by shelving the battery in the atmosphere of specific temperature after initial charging or jar formation, and then additionally charging the battery at room temperature.
CONSTITUTION: A sealed lead-acid battery after initial charging or jar formation, is shelved at a temperature in the range of 50°C to 80°C. Then, the battery is additionally charge to a fully charged condition and shelved at normal temperature for a long period. When additionally charged after shelved at a high temperature and again shelved at normal temperature for a long period as aforementioned, the lead-acid battery becomes free from a substantial capacity drop or dispersion. Also, a drop in recovery capacity becomes small. It becomes possible, therefore, to obtain a lead-acid battery free from a substantial capacity drop and dispersion even after a long shelf period, and superior in capacity recoverability.
SANO AKIHIKO
YOSHINO HARUMI
