| 摘要 |
<p>A lithium secondary battery comprises a negative electrode structure, an electrolyte and a positive cathode structure, the negative electrode structure comprising at least 40 % by weight of natural flake graphite, and said electrolyte comprising at least 10 % by weight of propylene carbonate based on the weight of the solvent and salts of the electrolyte system. Natural flake graphite is compatible with propylene carbonate containing electrolytes, thereby forming stable battery configurations. The negative electrode material shows a low initial capacity loss of less than 100 mAh/g, i.e. 22 % of the initial capacity, a high reversible capacity of more than 340 mAh/g, good cyclability and flat discharge voltage profile. Natural flake graphites allow construction of electrode structures of densities higher than 0.8 g/cm3, compared to the artificial graphites of an electrode density lower than 0.7 g/cm3 with the same configuration. The higher gravimetric density of the negative electrode allows a higher energy density of the complete battery.</p> |
