Method and apparatus for charging and testing batteries

Claim 1

A battery charging apparatus for charging a rechargeable battery, comprising: (a) microprocessor means for controlling the operations of said apparatus; (b) software means for instructing said microprocessor means to control the sequence of said operations; (c) memory means connected to said microprocessor means for storing said software instructions and predetermined data and cell characteristics corresponding to said battery; (d) digital to analog converter means connected to said microprocessor means for converting digital signals from said microprocessor means to analog signals; (e) direct current power generator means, connected to said digital to analog converter means for producing controllably varying charging current or voltage to said battery for a predetermined period of time as required by said microprocessor means and for charging said battery automatically with a charge input at any rate until the battery charge voltage equals the estimated number of cells of said battery multiplied by a predetermined voltage which is characteristic of the battery; (f) a pair of output means of said apparatus, for connection with said battery; (g) current sensor means, connected to said output means for measuring the current passing through said output means to and from said battery; (h) voltage measuring means for measuring the voltages of said battery, current sensor and direct current power generator means while said power generator means supplies a controllably varying charging current or voltage and for measuring open circuit voltage of said battery and estimating the number of cells possible for the measured open circuit voltage; (i) analog to digital converter means, connected to said voltage measuring means, for converting the analog signals from said voltage measurements to digital signals for transmission to said microprocessor; (j) second software means for analyzing said current and voltages and for determining number of cells, capacity, state of charge and defects in said battery; (k) actuator means for controlling the electrical circuits connecting said sensors, said direct current power generator means and said battery; (l) control means coupled to said power generator means for controlling the voltage and current supplied by said power generator means to said battery; and (m) display means, controlled by said microprocessor means for indicating status of said battery and said apparatus, and advice.