Development of overcharge tolerance in Li/FeS and Li/FeS/sub 2/ cells

Conference · Fri Jan 01 04:00:00 EST 1988

OSTI ID:6896200

Kaun, T D; Holifield, T F; Nigohosian, M; Nelson, P A

An innovative application of a self-discharge mechanism for molten-electrolyte Li-alloy/FeS/sub x/ cells has led to the development of overcharge-tolerant cells. Conventional Li-alloy/FeS/sub x/ battery cells require an electronic charger/equalizer. Two versions of the cell have been demonstrated: LiAl+10 Mol% Li/sub 5/Al/sub 5/Fe/sub 2//LiCl-LiBr-KBr (BN, MgO)/FeS/sub 2/ (operated at 400/degree/C) and LiAl+10 mol% Li/sub 5/Fe/sub 2//LiF-LiCl-LiBr(MgO)/FeS (operated at 475/degree/C). These cells exhibit a unique combination of overcharge capacity and extended trickle-charge tolerance at 2--5 mA/cm/sup 2/. The basis for the self-discharge is diffusion of reduced lithium species across the separator by a lithium-shuttle mechanism that is controlled by the Li-activity of the Li-alloy electrode. A bimodal self-discharge rate (a 20-fold increase toward the end of charge) results from a 150--250 mV step increase in Li-activity. Cells having overcharge tolerance have operated with stable performance for greater than 200 cycles. The overcharge tolerance rates are sufficient for battery cells to exhibit built-in charge/equalization capability. 11 refs., 6 figs.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6896200
• Report Number(s): CONF-881061-10; CONF-881061-10; ON: DE89003952
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
250900* -- Energy Storage-- Batteries
ALLOYS
BATTERY CHARGING
CAPACITY
CHALCOGENIDES
DATA
ELECTRIC BATTERIES
ELECTRIC DISCHARGES
ELECTROCHEMICAL CELLS
ELECTRODES
INFORMATION
IRON COMPOUNDS
IRON SULFIDES
LITHIUM ALLOYS
NUMERICAL DATA
SULFIDES
SULFUR COMPOUNDS
TOLERANCE
TRANSITION ELEMENT COMPOUNDS