Abstract: An apparatus balances a discharge in parallel battery configuration by having a battery pack (a) with a first battery system and a second battery system in parallel configuration, and a pulse width modulation device and (b) being interconnectable to a load. Each of the first and second battery systems has, in series and in order, a first voltage sensor, a resistor, a second voltage sensor, a string of battery cells, and a switching device. The first and second voltage sensor, in each battery system, measures an electrical current, used to calculate the voltage drop across each resistor. The voltage drop values for each battery system determine whether the pulse width modulation device alters or maintains the pulse width modulation applied to each battery system's switching device. By maintaining or altering the pulse width modulation applied to each switching device, the apparatus effectively balances the electrical current discharge from each battery system.

Abstract: A lithium thionyl chloride cell having, in a can, a cathode collector, a solution of lithium tetra-chloroaluminate (LiAlCl4) in thionyl chloride (SOCl2), and a lithium alloy anode. The lithium alloy anode has lithium and an alloy material selected from the group consisting of magnesium and aluminum. The composition of lithium in relation to the alloy material ranges from 95:5 to 50:50, by weight, such that the total capacity of the lithium plus the alloying material is greater than the capacity of the thionyl chloride and at the same time the capacity of the lithium alone is less than or equal to the capacity of the thionyl chloride.