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BAJ Recommendation Regarding the Reuse of Lithium-Ion Secondary Batteries

The concept of promoting the reuse of lithium-ion secondary batteries is spreading, from the viewpoint of using resources effectively. The battery has developed as a power supply for portable devices, and its applications are extending into the energy field, such as electrical storage devices and driving systems for cars, etc. after switching to a low-carbon society starts as an action against global warming.

However, it is said that the development history of lithium-ion secondary batteries was narrow and difficult, amid a dilemma between convenience brought by high energy and assurance of safety. We have overcome this situation while maintaining a very delicate balance between the two. Accordingly, the battery requires us to fully understand its characteristic advantages and disadvantages to take sufficient safe handling measures.

The Battery Association of Japan, which has led the world in the development and production of lithium-ion secondary batteries and made a contribution in the fields of technology, quality, and safety, now summarizes the concepts of reusing the batteries based on repeated reviews.

Recommendations have been made in accordance with the following basic concepts:
1) ensuring the personal safety,
2) recycling and effectively using resources,
3) reducing business risks of the entities related to lithium-ion secondary batteries and developing their businesses, and
the hope that lithium-ion secondary batteries will continue to contribute to the world.

BAJ Recommendation Regarding the Reuse of Lithium-Ion Secondary Batteries

July 10, 2014
Battery Association of Japan

1. Recommended concepts of reuse

  Consumer or Industrial use
Authorized use(A battery can have more than one application from the beginning.) Unauthorized use(Application not intended initially)
Battery system or assembly (e.g. battery pack or module with a special protective function*5) Permitted
*1
Prohibited
*3
Single battery (e.g. cell with a special protective function*5 removed) Prohibited
*2
Prohibited
*4

*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.

<Glossary>

*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)