| 摘要 |
Conventional lithium polymer batteries obtained by impregnating a graphite negative electrode with a precursor of polymer solid electrolyte and then conducting polymerization, have a problem that radicals generated during the polymerization are consumed by the graphite. Consequently, some monomers remain unreacted, thereby hindering the thus-obtained polymer battery from having an excellent long-term reliability. Conventional polymer batteries using physically crosslinked gel have a problem that a leakage occurs on abnormal occasions since the gel liquefies at high temperatures. A lithium polymer battery of the invention comprises a positive electrode, a negative electrode containing a negative electrode active material that is a carbon material powder, and a chemically crosslinked gel electrolyte. The carbon material powder is a mixture of at least two composite graphite material powders wherein a low-crystalline carbon material adheres to the surface of high-crystalline graphite particles. The composite graphite material powders are different from each other in values of physical properties. Accordingly, a battery having a high energy density and an excellent long-term reliability (excellent cycle characteristics) can be obtained. |
