Boss don't trust rechargeable batteries, this is just from one of four systems so far this year : r/livesound
Ansmann Rechargeable 9V Battery 300mAh pre-Charged Low Self Discharge 9Volt NiMH Rechargeable Battery (6-Pack) + Batterybox for 9V : Health & Household
Buy ENVIE (9v Infinite) Ni-Mh 300mAh Capacity Ready to Use Rechargeable BaOnline Best Prices
Varta Powerone P7/8H 8.4V(9 Volt Case) Ni-MH Battery 5122-210-501
Varta V7/8H, Accu Power 8.4 Volt 200mAh 9 Volt Style NIMH Battery
Shopping:NM1604-1 NiMH Rechargeable 9V Battery
Pile 9V rechargeable NIMH Varta 200mAh 6LR61
Replace standard batteries - Exact replacement for standard 9V sized batteries. Replace your alkaline batteries with these NiMH 9V rechargeable batteries. Standard 9V rectangular size battery dimensions: 48mm x 26mm x 16mm (H x L x W). Money saving eco-friendly - One of the most cost-effective batteries, Tenergy NiMH 9 volt battery can be recharged up to 1000 times. They will pay for themselves after 10 cycles.
Tenergy 4-Pieces Nimh High Capacity Rechargeable Battery, 9V, 250 mAh
Charges 2 or 4 AA, AAA, C or D size NiMH batteries or 1 or 2 9 V NiMH batteries overnight. Red LED charge indicators go off when charging is complete. Reverse polarity protection against damage from incorrectly installed batteries. UL Listed.
Energizer CHFCV Battery Charger
RAYOVAC AL-9V replacement battery (rechargeable)
Replace standard batteries - Exact replacement for standard 9V sized batteries. Replace your alkaline batteries with these NiMH 9V rechargeable batteries. Standard 9V rectangular size battery dimensions: 48mm x 26mm x 16mm (H x L x W). Money saving eco-friendly - One of the most cost-effective batteries, Tenergy NiMH 9 volt battery can be recharged up to 1000 times. They will pay for themselves after 10 cycles.
Tenergy 4-Pieces Nimh High Capacity Rechargeable Battery, 9V, 250 mAh