Using Rechargeable AA/AAA Batteries in an Outdoor Handheld Device

Rechargeable AA batteries can be used in any outdoor handheld unit that accepts AA batteries. However, most devices cannot be used to recharge the batteries.¹ When the device is connected to an external power supply, the device will rely on the external power to operate but will not charge or use the batteries that are inserted. The batteries will need to be removed and charged through an external charger. When using third party NiMH batteries, it is recommended to change the Battery Type setting on the device to get more accurate estimates on remaining battery life. This setting is typically found under Setup > System. Within this setting there are two types of NiMH batteries to choose from.

Traditional NiMH

These batteries must be charged before their first use and have a higher rate of self-discharge when compared to pre-charged NiMH batteries, meaning they may need to be recharged more often between uses.

Precharged NiMH

Sometimes advertised as "Ready-to-Use" or "Low Self-Discharge" (LSD), these batteries have a significantly lower rate of self-discharge when compared to traditional NiMH batteries. This means that they will retain their charge for longer between uses.

¹ The Astro ®430 and Astro® 900 dog tracking handhelds, GPSMAP® 64/65 series, GPSMAP® 66s/st, and Oregon® 600/700 series outdoor handhelds will recharge the Garmin NiMH Battery Pack.