Rebalancing of lithium/silver vandium oxide (Li/SVO) cells for improved performance

DETAILED DESCRIPTION OF THE INVENTION Batteries or cells are volumetrically constrained systems.
The amounts of components that go into a battery (cathode, anode, separator, current collectors, electrolyte, etc.
) can not exceed the available volume of the battery case.
In addition, the appropriate amount of some components depends on the amount of other components that are used.
These components must be "balanced" to provide discharge to the extent desired.
For example, in a cathode limited Li/SVO battery (all conventionally balanced Li/SVO batteries known to date are of this type) such as is used in a defibrillator application, the capacity (Q.
sub.
+) of the cathode must not exceed the capacity (Q.
sub.
-) of the anode.
Cathode limited cells are also conventionally used in virtually all battery powered implantable medical devices such as heart pacemakers because of the proven reliability of their discharge over the long periods during which they are implanted.
The volume occupied by the other battery components also depends on the cathode capacity (Q.
sub.
+) as reflected by the amount of cathode material in the battery.
The amount of electrolyte depends on the amount of cathode material and the amount of it to be discharged since the cathode material swells as the battery is discharged and requires more electrolyte to fill the additional cathode volume.
The volume of the separator and current collector depends on the area of the electrodes.
The area of the electrodes depends on the area required for consistent pulse output as the battery is discharged.
All of these components must be adjusted for a given battery volume.
Although a variety of battery configurations and constructions are possible for Li/SVO batteries, a coiled or wrapped configuration will be discussed herein as an exemplar of a conventional Li/SVO battery for use with the invention.
The invention is of course applicable to any configuration and construction.
With reference to FIG.
1 such an exemplar battery construction is described