What Happens When an Electric Vehicle Battery Is Left Empty for Too Long

A battery is a core component of an electric vehicle, determining performance and range. Therefore, keeping the battery within a safe charging level is essential. One condition to avoid is leaving an electric vehicle battery in a discharged or near-empty state for an extended period. Budi Darmawan Jantania, Vice Country Director of the Chery Business Unit at PT Chery Sales Indonesia, said this can pose risks to the high-voltage battery system. ‘If the electric vehicle battery is left too long in a discharged state, there is a risk of over-discharge. This condition can trigger imbalance among cells within the high-voltage battery,’ he told Kompas.com on Wednesday 4 March 2026. In the worst-case scenario, damage to the high-voltage battery system could occur, potentially requiring intensive repairs or even replacement of the battery unit. ‘Therefore, keeping the State of Charge (SOC) within a safe range is crucial to maintain the health and lifespan of the electric vehicle’s battery,’ he said. Arif Nugroho, Service Manager at Hyundai Kalijaga Cirebon, concurred. He explained that if an electric vehicle battery is left flat for too long, it can lead to deep discharge. ‘If deep discharge occurs, the Battery Management System (BMS) may lock the system as a protective measure,’ he noted. In more extreme cases, deep discharge can cause permanent degradation of the lithium-ion cells inside the battery. If this happens, the vehicle typically requires a special recovery procedure conducted at an authorised workshop. ‘Therefore, it is very important to keep SOC above 20 percent for normal use,’ he added. By keeping the battery level within a safe range, the performance and lifespan of an electric vehicle’s battery can be maintained more optimally.