BATTERY UNIT AND BATTERY MONITORING DEVICE

To provide a battery unit and a battery monitoring device, which can grasp a battery state after a replaceable battery unit has been removed.SOLUTION: The battery unit includes: a battery portion (battery cell 22) that can supply an electric power to an external load in a state in which the battery unit is attached to the external load; a load portion (voltage equalization circuit 80) that is connected to the battery portion; a measurement portion (monitor IC31) that measures at least one of an electric current flowing through the load portion and a voltage applied to the load portion; and a control portion (radio IC32) that is configured to cause the battery portion to operate as an electric power source in a state in which the battery unit is detached from the external load, also causes the battery portion to pass an electric current to the load portion at a predetermined timing, and acquires a measurement result measured by the measurement portion at this time.SELECTED DRAWING: Figure 7 【課題】交換可能な電池ユニットが取り外された後に電池状態を把握することが可能な電池ユニット及び電池監視装置を提供する。【解決手段】電池ユニットは、外部負荷に対して電池ユニットが取り付けられた状態において、外部負荷に電力を供給可能な電池部（電池セル２２）と、電池部に接続された負荷部（電圧均等化回路８０）と、負荷部を流れる電流及び負荷部に印加される電圧のうち少なくともいずれか一方を測定する測定部（監視ＩＣ３１）と、外部負荷に対して電池ユニットが取り外された状態において、電池部を電源として動作するように構成されるとともに、所定のタイミングで電池部から負荷部に電流を流させ、その時に測定部により測定された測定結果を取得する制御部（無線ＩＣ３２）と、を備える。【選択図】図７