BATTERY SYSTEM

• Main Authors: SASAKI TSUYOSHI, TOMURA SHUJI, HIROTA YASUKI, KOGA TATSUYA
• Format: Patent
• Language: English; Japanese
• Published: 18.01.2016
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

PROBLEM TO BE SOLVED: To provide a battery system capable of determining the amount of active lithium which cannot be dissolved in lithium ions due to breakage of active lithium although active lithium can be normally dissolved in lithium ions.SOLUTION: A controller (40) calculates the total amount (Q) of active lithium when a precipitation reaction and a dissolution reaction are performed on the basis of reaction current when the precipitation reaction and the dissolution reaction are performed. The ratio (γ) between the total amount of active lithium and the amount of active lithium which is generated and does not conduct the dissolution reaction due to breakage of active lithium can be calculated on the basis of at least one of a current value under charging of a lithium ion secondary battery and a duration time under charging. The ratio increases as the current value under charging is larger, and the ratio increases as the duration time is longer. The amount (Q) of active lithium which does not conduct the dissolution reaction can be calculated by calculating the total amount (Q) of active lithium and the ratio (γ). 【課題】 活性リチウムは、リチウムイオンに溶解することができるが、活性リチウムの切断によって、溶解できない活性リチウムが発生することがある。【解決手段】 コントローラ（４０）は、析出反応および溶解反応が行われたときの反応電流に基づいて、析出反応および溶解反応が行われたときの活性リチウムの総量（Ｑ３）を算出する。活性リチウムの総量と、活性リチウムの切断によって生成され、溶解反応が行われない活性リチウムの量との比率（γ）は、リチウムイオン二次電池の充電時の電流値および、充電時の継続時間のうちの少なくとも一方に基づいて算出できる。充電時の電流値が大きいほど比率が高くなり、継続時間が長いほど比率が高くなる。活性リチウムの総量（Ｑ３）および比率（γ）を算出すれば、溶解反応が行われない活性リチウムの量（Ｑ３＿ｂ）を算出できる。【選択図】 図５