questioned. On the other hand, as for cobalt, resources security by collection and recycle is important. As just mentioned, the directions of management of both substances are different. Cadmium is produced as a by-product of zinc smelting in Japan and the deficit is imported. For these ten years, the amount of import of cadmium greatly has decreased from 2,500t to 260t, whereas the domestic production has been roughly flat. These reasons are that the domestic production of NiCd batteries has decreased sharply and several domestic NiCd battery factories moved to China.

As cadmium is produced as a by-product of the domestic zinc smelting, the production of cadmium will increase as far as the production of zinc continues. (Cadmium from zinc production alone is approximately 2,500t a year.) The domestic production of zinc is remaining at the same level, and the demand of cadmium is decreasing sharply in Japan, and the tendency is expected to continue. Therefore, the surplus cadmium is expected to increase in the future.

On the other hand, as for cobalt of the production containing lithium-ion battery, notebook computer whose battery is heavy relatively in weight makes the largest contribution, and followed by others, a cell-phone, a video camera for a lithium ion battery incorporation product. Around half of the production after use was supposed to be put in dead storage incrementally, which suggests a need for the appropriate collection. Additionally, cobalt density varies among makers and products, the evaluation of resource performance and recycle value is difficult. Therefore, development of stable circulation use system is a big issue.

(3) Verification of the subject of batteries from the viewpoint of life cycle

Especially in Europe, LCA is highly developed as an evaluation technique of a battery. The evaluation shows that the environmental impact of a rechargeable battery is lower than a primary battery, and that both a primary battery and a rechargeable battery are desirable to be recycled. There is much amount of the primary battery used in Japan compared with foreign countries, that is, throwing away of a battery has permeated. Then, the energy residual quantity of the thrown-away primary battery was investigated. As a result, it turned out that there is clearly much energy residual quantity compared with U.K. or Taiwan, and that an improvement of usage and the shift to a rechargeable battery, the promotion of “2R (reduce & reuse)” of a battery, are required.

(4) International comparison of the policy of circulation and disposal of small batteries

Especially in Denmark and Switzerland, as foundations of the recycling system, three kinds of flow - material flow, money flow, and information flow - (How and how much flows between involved bodies?) was described, and the features were summarized. As a result, we confirmed that even if each country has the similar framework based on producer responsibility, there is a big difference in the way to give the incentive to persons involved and the burden of expense. Furthermore, comparing the system of the two countries with that of Japan, the following results were obtained;

1) Although only the rechargeable battery was an object in Japan, all the batteries also including a primary battery are collected based on an expanded producer responsibility in these countries.

2) Expense for collection of the battery is contained in the price.

3) The role to be played by local government in collection of waste is large.

4) Producers pay the expense which local governments use for collection of waste, and there is an incentive of collection.

• Keywords: battery, collection, recycling, policy, flow analysis