Patent ID: 8675328
Filing Date: 2014-03-18
Classification: G01R,H02H,H02J

Abstract:
1. A multiply redundant battery-recharge protection circuit, for use in preventing a rechargeable battery with one or more cells from being overcharged by a solar panel array, said multiply redundant battery protection circuit comprising: a first group and a second group of comparator circuits, each group having a respective comparator circuit for each of the one or more cells of the battery, said respective comparator circuit of each of said first and second groups independently supplying a digital output if a respective cell is determined to be overcharged by being at or exceeding an upper threshold voltage; a first logic gate and a second logic gate, said first and second logic gates providing a respective “or” operation for said comparator circuits of said first and second groups, each of said logic gates supplying a digital signal when one comparator circuit within its respective group supplies said digital output; a first P-channel field effect transistor wired in parallel with a second P-channel field effect transistor, with each said first and second field effect transistors having its gate terminal being respectively coupled to said first logic gate to be capable of receiving said digital output; a third P-channel field effect transistor wired in parallel with a fourth P-channel field effect transistor, with said third and fourth field effect transistors being wired respectively in series with said first and second field effect transistors, and with each said third and fourth field effect transistors having its gate terminal being respectively coupled in parallel to said second logic gate, to independently receive said digital output therefrom; a first relay and a second relay; said first relay being coupled in series with said third field effect transistor; said second relay being coupled in series with said fourth field effect transistor; each said first and second relays having coils being respectively energized to cause isolation of the battery upon said first and third field effect transistors turning on after receiving said digital signal of said first and second logic gates and said second and fourth field effect transistors turning on after receiving said digital signal of said first and second logic gates; and wherein said circuit provides multiply redundant battery-recharge protection comprising: redundantly assessing said determination of overvoltage; redundantly triggering said recharge isolation of the battery; and preventing inadvertent isolation and non-charging, occurring absent said overvoltage, through redundancy with said first and second isolation relays.