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ngrant · 02-08-2010, 11:10 PM

The JBL's battery meter is calibrated for regular alkaline batteries, so when you are using rechargeables the battery indicator is NOT accurate. It shows a high charge remaining for a long time, then goes down very suddenly to two bars or one then the device shuts off, seemingly without warning. How soon this happens will depend on many factors - e.g. the rated capacity of your rechargeables, how old they are, how many times they have been charged, and so on.

According to other reports on this forum, the early/abrupt shutting down can also cause the JBL to have problems restarting and then requires a reset or even reloading of the firmware. I had to do the reset once.

I have 5 year old Powerex rechargeables rated at 2500 mAh (yes, they DO still work!) which give me about 10 hours of reading on the JBL from a full charge; I no longer wait on the device to shut down, but replace the batteries after about 8 hours or when the indicator shows 2 bars. Or I use regular alkaine batteries (bought cheaply in bulk). Better safe than sorry, that's my philosphy. And with 2 sets of rechargeables, I always have a set fully charged and ready to go - and lots of spare alkalines too.

Since I have a lot of gadgets I always keep lots of batteries on hand, so it's not a problem for me. Just something to be aware of.

02-08-2010, 11:10 PM	#5
ngrant Gadget Lover Posts: 527 Karma: 5063196 Join Date: Nov 2009 Location: MS, USA Device: Oasis 2, Mobiscribe Origin, Fire HD tablets	Rechargeables vs Alkaline batteries The JBL's battery meter is calibrated for regular alkaline batteries, so when you are using rechargeables the battery indicator is NOT accurate. It shows a high charge remaining for a long time, then goes down very suddenly to two bars or one then the device shuts off, seemingly without warning. How soon this happens will depend on many factors - e.g. the rated capacity of your rechargeables, how old they are, how many times they have been charged, and so on. According to other reports on this forum, the early/abrupt shutting down can also cause the JBL to have problems restarting and then requires a reset or even reloading of the firmware. I had to do the reset once. I have 5 year old Powerex rechargeables rated at 2500 mAh (yes, they DO still work!) which give me about 10 hours of reading on the JBL from a full charge; I no longer wait on the device to shut down, but replace the batteries after about 8 hours or when the indicator shows 2 bars. Or I use regular alkaine batteries (bought cheaply in bulk). Better safe than sorry, that's my philosphy. And with 2 sets of rechargeables, I always have a set fully charged and ready to go - and lots of spare alkalines too. Since I have a lot of gadgets I always keep lots of batteries on hand, so it's not a problem for me. Just something to be aware of.