Research and development of advanced lead-acid batteries for electric vehicle propulsion
For this contract period, the major objective was the demonstration of flow-by technology that provides a specific energy is excess of 40 Wh/kg on the Simplified Federal Urban Driving Schedule SFUDS(79), and a life of at least 200 cycles to 80% depth-of-discharge. The key challenge was to improve life without compromising the high levels of specific energy, ranging from 40 to 53 Wh/kg, that had been demonstrated in previous cells. The technology areas to be investigated were: (1) maximizing the PAM mass fraction, (2) dynamic compression to preserve the morphological integrity of the PAM, and (3) continued optimization of the core cell technology. As the result of extensive experimentation, it became known that the power oscillation character of the SFUDS was the primary life limiting factor. Therefore, the program emphasis was shifted towards increased testing of the baseline cell design to determine the full impact of the SFUDs type profile, with particular interest in determining the failure mode mechanism(s) affecting the positive active material. Results from cycle life testing clearly identified the positive electrode, or cathode, as the life limiting component. Specifically, polarization of the electrode during the 50 and 79 W/kg power steps of the SFUDS results in extremely depressed cathodic potential, as low as 0.3 volts versus the Hg/Hg{sub 2}SO{sub 4} reference electrode. This polarization effect is believed to be responsible for the characteristic decline in extractable capacity that the cathode displays on SFUDS cycle testing. The exact mechanism responsible for this capacity decline is unknown, but it is strongly suspected that a catastrophic change occurs in the positive active material (PAM) morphology, resulting in loss of reactive surface area and limited electron transfer and ionic transport capability.
- Research Organization:
- Johnson Controls Battery Group, Inc., Milwaukee, WI (United States)
- Sponsoring Organization:
- DOE; USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-31109-ENG-38; AC02-86NV10509
- OSTI ID:
- 5709602
- Report Number(s):
- DOE/CH-10509-02; ON: DE92010394
- Country of Publication:
- United States
- Language:
- English
Similar Records
Post-test analysis of 3ET205 module LC03TL12 from chloride motive power
Post-test analysis of 3ET205 module LC03TL12 from chloride motive power
Related Subjects
250902* -- Energy Storage-- Batteries-- Performance & Testing
33 ADVANCED PROPULSION SYSTEMS
330300 -- Advanced Propulsion Systems-- Electric-Powered Systems
CATHODES
COMPARATIVE EVALUATIONS
DOCUMENT TYPES
ELECTRIC BATTERIES
ELECTRIC-POWERED VEHICLES
ELECTROCHEMICAL CELLS
ELECTRODES
EVALUATION
LEAD-ACID BATTERIES
PERFORMANCE TESTING
PROGRESS REPORT
SERVICE LIFE
TESTING
VEHICLES