EcoFlow WAVE 3 Add-on Battery (Recommended Accessory) Eecoflow.com · EcoFlow US $649.00 $649.00 + shipping not listed ✓ Price verified in the store on 11/04/2026 3:33 PM 🛒 Buy at ecoflow.com 🔔 Alert me when it drops You pay securely in the store. We never ask for your payment details. · Wrong price? Gevilens is free. Stores may pay us when you buy through our links — your price stays the same.