Lead-acid battery construction
AssigneeCalifornia Institute of Technology
InventorJohn J. Rowlette
Life of this patent
Estimating the term…
Abstract
The power characteristics of a lead-acid battery are improved by incorporating a dispersion of 1 to 10% by weight of a thermodynamically stable conductivity additive, such as conductive tin oxide coated glass fibers (34) of filamentary glass wool (42) in the positive active layer (32) carried on the grid (30) of the positive plate (16). The avoiding of positive plate reversal to prevent reduction of the tin oxide is accomplished by (a) employing an oversized positive plate and pre-charging it; (b) by pre-discharging the negative plate; and/or (c) by placing a circuit breaker (26) in combination with the plates (16, 18) and terminals (22, 24) to remove the load when the voltage of the positive plate falls below a pre-selected level.
Claims13
In a lead-acid battery cell comprising--an electrolyte impervious enclosure receiving a body of liquid acid electrolyte;
- a first electrode containing negative active lead material immersed in the body of electrolyte;
- a second electrode immersed in the body of electrolyte and containing positive active lead oxide material having dispersed therein 1 to 10% by weight of particulate additive that is insoluble in the acid electrolyte, having a conductivity similar to the positive active material, and being thermodynamically stable during charge and discharge of the positive active material;
- a positive and a negative terminal;
- and, means connecting the electrodes to their respective terminals, the improvement to prevent plate reversal of the electrodes with attendant reduction of the particulate additive comprising:
- the positive electrode being an oversized electrode with respect to the size of the negative electrode and being initially in a precharged condition such that a plate reversal state is rendered chemically impossible.
In a lead-acid battery cell comprising--an electrolyte impervious enclosure receiving a body of liquid acid electrolyte;
- a first electrode containing negative active lead material immersed in the body of electrolyte;
- a second electrode immersed in the body of electrolyte and containing positive active lead oxide material having dispersed therein 1 to 10% by weight of particulate additive that is insoluble in the acid electrolyte, having a conductivity similar to the positive active material, and being thermodynamically stable during charge and discharge of the positive active material;
- a positive and a negative terminal;
- and, means connecting the electrodes to their respective terminals, the improvement to prevent plate reversal of the electrodes with attendant reduction of the particulate additive comprising:
- the negative electrode being initially in a pre-discharged condition with respect to the positive electrode such that a plate reversal state is rendered chemically impossible.
In a lead-acid battery cell comprising--an electrolyte impervious enclosure receiving a body of liquid acid electrolyte;
- a first electrode containing negative active lead material immersed in the body of electrolyte;
- a second electrode immersed in the body of electrolyte and containing positive active lead oxide material having dispersed therein 1 to 10% by weight of particulate additive that is insoluble in the acid electrolyte, having a conductivity similar to the positive active material, and being thermodynamically stable during charge and discharge of the positive active material;
- a positive and a negative terminal;
- and, means connecting the electrodes to their respective terminals, the improvement to prevent plate reversal of the electrodes with attendant reduction of the particulate additive comprising:
- an electrical circuit breaker combined with the battery cell and electrically disposed in the connection between the electrodes and the terminals, said circuit breaker being adapted to sense the voltage on the positive plate and electrically disconnect a load attached thereto from the cell when the voltage on the positive plate drops below a pre-selected level whereby a plate reversal state is rendered impossible.
An improved lead-acid battery cell comprising:
- (a) an electrolyte impervious enclosure containing a body of liquid acid electrolyte;
- (b) a first electrode containing negative active lead material immersed in said body of electrolyte;
- (c) a second electrode containing positive active lead oxide material immersed in the body of electrolyte and having dispersed therein 1 to 10% by weight of particulate additive that is insoluble in said acid electrolyte, has a conductivity similar to said positive active material, and is thermodynamically stable during charge and discharge of said positive active material;
- (d) a positive terminal;
- (e) a negative terminal;
- (f) means connecting said electrodes to their respective ones of said terminals;
- and,
- (f) means for preventing plate reversal of said electrodes with attendant reduction of said particulate additive.
Dependencies are inferred from the claim text.