EcoFlow DELTA Max Smart Extra Battery (200Wh) More of DELTA Max Double runtime with this add-on battery that plugs into any DELTA Max portable power station. Add up to two Extra Battery units for a total capacity of 6048Wh. Convenient recharging DELTA Max and its Extra Battery charge and discharge in unison. Whether you’re recharging DELTA Max from solar panels, AC outlets, a vehicle, or our Smart Generator, the DELTA Max Extra Battery will recharge alongside. Independent in emergencies The extra battery even recharges directly from EcoFlow’s Smart Generator without DELTA Max. That’s more recharging options to fit any situation. LCD screen Get all the info on battery percent, time until full, time until empty, and more on the DELTA Max Extra Battery LCD screen. Check the battery’s status anywhere on the EcoFlow app.