Stearic Acid → Octadecanoic acid, silver(1+) salt (1:1)

7.5 g of stearic acid and 1.2 g of sodium hydroxide were added to 300 ml of water and sufficiently stirred until they were completely dissolved. 5.2 g of silver nitrate was added thereto, and the result was stirred for 3 hours. White powder on the surface of the result was collected and washed three times each with distilled water and with methanol to obtain silver stearate. An anode active material was prepared as in Example 1, except that silver stearate was used instead of nickel stearate, the molar ratio of silver to silicon was 0.2:1, the weight ratio of silicon to graphite was 0.5:1, and the carbon layer was 5.2 wt % of the anode active material.