Improved carbon anode materials for lithium-ion cells

Conference · Wed Jul 01 04:00:00 EDT 1998

OSTI ID:20019194

Flynn, J; Marsh, C

Several carbon materials have been studied for suitability as anode materials in lithium-ion cells. Carbons that have been included in this evaluation are three grades of commercially available mesophase carbon microbeads (MCMB) 6-28, 10-28 and 25-28, two specially prepared mesophase fibers (Amoco), a foreign mesophase fiber and KS-15 graphite (Lonza). Differences in cycling behavior between the three types of MCMB material are shown. Data of full lithium-ion cells demonstrate the effect that the choice of carbon material has on the cell discharge voltage and capacity. Lithium reference electrode experiments in full cells (3.0--4.0Ah capacity), elucidate the dynamics under several charge/discharge regimes and provide a comparison between the performance of carbon fiber and graphite anode materials. These test results indicate that the fibers can be charged at significantly higher rates than graphite without showing polarization at the anode. Full and half cell data also demonstrates the high coulombic efficiencies of the mesophase materials and first cycle efficiencies as compared to graphite. A comparison of two mesophase materials with different textures in full cells under strenuous cycling conditions shows significant differences in capacity retention. SEM photos of fibers showing the different textures are also presented.

• Research Organization: Yardney Technical Products, Inc., Pawcatuck, CT (US)
• Sponsoring Organization: US Department of the Air Force
• OSTI ID: 20019194
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
36 MATERIALS SCIENCE
ANODES
CARBON
CARBON FIBERS
COMPARATIVE EVALUATIONS
ELECTROCHEMISTRY
METAL-NONMETAL BATTERIES
PERFORMANCE
TEXTURE