Racepow 4000mAh 4S1P 10C is a Liion battery with an excellent price/performance ratio. The battery is suitable for 4-5" drones, where it can provide a long flight time. The advantage of Liion batteries is their higher energy density - they can offer higher capacity at a lower weight. The downside is lower discharge currents. You therefore need to use the throttle gently. Liion batteries are therefore especially suitable for calm flying - cruise or long-range. The minimum cell voltage is 2.5V, but we recommend landing with a slight reserve at around 2.7V per cell.
Before use, read Rules for safe use of Li-ion batteries.