1. Recommended concepts of reuse
*1 Presently, in a system*6 that consists of lithium-ion batteries (including a battery system) and a device using lithium-ion batteries, the both shall have a one-to-one relationship in order to guarantee the safety of the system*6 using lithium-ion batteries.
It is possible to build up a system*6 for authorized use in which more than one device (application) has one common battery with the one-to-one relationship shown above guaranteed.
*2 Application resulting from the disassembly of a battery pack or module into single batteries and the reconstruction of a system*6 for authorized use with a battery assembly reconstructed from the single batteries.
*3 Application resulting from the reconstruction of a system*6 for unauthorized use with a battery pack or module maintained.
*4 Application resulting from the disassembly of a battery pack or module into single batteries and the reconstruction of a system*6 for unauthorized use with a battery assembly reconstructed from the single batteries.
2. Reason for opposition to the unauthorized products
We guarantee the safety of a system*6 using lithium-ion batteries, by verifying the safety of single batteries, controllers, and their close combination of mutual safety functions, assuming operating environments and applications.
To do this, the battery and device manufacturers shall exchange enough information with each other and carry out a risk assessment before they produce and sell their products. Therefore, we strongly recommend that use of the unauthorized products is prohibited, because they are not verified.
3. Reason for the opposition to reconstructed battery assembly after disassembling a battery assembly into single batteries
Used systems*6 show different levels of degradation in capacity and different chronological changes for each battery pack, module, or its single battery (single cell). With our current technology, however, it is difficult to guarantee the safety when reconstructing a battery pack, module, or battery system from the disassembled single batteries. Therefore, we strongly recommend that use is prohibited.
4. Battery Association of Japan's concepts
As shown in Sections 2 and 3 above, the Battery Association of Japan strongly recommends that use is prohibited for the reuse*7 in cases *2 to *4 of the table because the safety is not guaranteed and there are some risks bringing about unsafe factors to consumers and society.
However, this strong recommendation does not prevent the companies concerned from making efforts to develop safe products and technology in the future, even in cases *2 to *4.
*5 special protective function: Refers to the function of monitoring and controlling the safety of lithium-ion batteries, such as a battery management unit (BMU) or a battery management system (BMS). There are two cases: one is a case where the function is built in a battery pack or module, and the other is a case where it is incorporated into a device that uses lithium-ion batteries.
*6 system: Refers to a battery system (battery assembly) and a whole device using batteries, both being designed to guarantee the safety of the lithium-ion battery.
*7 reuse: Means that a used product is collected and treated properly as necessary for reuse as another product or for the use of its recyclable parts (excerpt from 3R Policies by the Ministry of Economy, Trade and Industry). Therefore, we allow a lithium-ion battery to be reused only in case *1 (battery assembly reused in an authorized product) of the table, provided it is treated properly.
*8 others: Refer to JIS C 8712 (IEC62133) and JIS C 8715 (IEC62619).
For more information about the JIS, access the website of the Japanese Industrial Standards Committee (JISC)