德国采购需求：电池存储、便携式电池、内置电池、便携式充电器、便携式搅拌机、外置电池

We are looking for a flexible Energy Storage System (ESS) solution with ±5 MW charging/discharging capacity and approximately 20 MWh usable capacity. Our operational strategy focuses on charging during periods of negative electricity prices and discharging during peak demand hours. Key requirements include around 88% round-trip efficiency, a minimum SoC reserve of 10%, and a strict schedule-based operation, avoiding simultaneous charging and discharging. Please confirm your capability to meet our needs and explore the connection details, such as metering systems and modular expansion options. We aim for seamless grid integration, with load management rules that prioritize charging only when prices are ≤ 0 €/MWh and enforce strict no-feed-in hours. Your insights on approvals for this operational model would also be appreciated.