VEHICULAR BATTERY SYSTEM

To provide a battery system which realizes opening or closing of a battery relay and can inhibit a user from feeling discomfort caused by operation sound made during opening or closing of the battery relay in a more secure manner.SOLUTION: There is provided a vehicular battery system equipped with a lithium-ion battery including battery cells 12, an external terminal 13a electrically connected to the battery cells 12, and a battery relay 14 which connects or disconnects electrical connection between the battery cells 12 and the external terminal 13a. The vehicular battery system is provided with: operation means 202 for operating a vehicle component 50; and control means 14, 90 which control the vehicle component 50. The vehicle component 50 is operated on the basis of an operation performed to the operation means 202 by the user and the battery relay 14 is opened or closed at same timing as operation timing of the vehicle component 50.SELECTED DRAWING: Figure 1 【課題】バッテリーリレーの開閉を実現しつつこれの開閉時の作動音によって利用者が違和感を覚えるのをより確実に抑制できるバッテリーシステムを提供する。【解決手段】バッテリーセル１２、バッテリーセル１２と電気的に接続された外部端子１３ａ、およびバッテリーセル１２と外部端子１３ａとの電気的な接続を接断するバッテリーリレー１４を備えるリチウムイオンバッテリーが搭載された車両のバッテリーシステムにおいて、車両部品５０を操作するための操作手段２０２と、車両部品５０を制御する制御手段１４、９０とを設け、操作手段２０２に対する利用者の操作に基づいて車両部品５０作動させるとともに、車両部品５０の作動タイミングと同じタイミングでバッテリーリレー１４を開閉する。【選択図】図１