The EHX 9v batteries are not “rechargeable”, but they CAN be recharged using a “universal battery charger”. The EHX battery is the very old fashioned carbon-zinc type battery which sounds better when used in certain analog effects – mostly overdrive, distortion, fuzz, and mostly germanium. But, carbon-zinc batteries have a short battery life and lose their power “smoothly” over time rather than quickly at the end. They CAN be recharged with a “universal battery charger”, but you have to be very careful. If you use a NiMH or Lithium charger to try to recharge them, they will explode. That’s why any manufacturer would rather just tell you that they are NOT rechargeable. Even though carbon-zinc can be recharged, they are not good for as many cycles as true rechargeable batteries like NiMH or Lithium. They will soon lose their ability to hold a charge.

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