The LR46xx handset uses 2 pieces of rechargeable Nickel-metal hydride (NiMH) battery cells that is capable of providing about 100 hours of standby time or 10 hours of talk time (the actual standby time and talk time should vary depending on operation circumstances).

The NiMH is also well-known for being immune to memory effect commonly found with other battery technologies.

Further information from wikipedia ...

NiMH batteries are commonly considered to have lower environmental impact than NiCd batteries, due to absence of toxic cadmium. The overall environmental impact of mining the various alternate metals that form the negative electrode may be more or less than cadmium, depending on the metal, mining method, and environmental practices of the mine.

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