Sansa Clip+: Only runs when plugged in, gives me an "ATA error: -2"

[dpitch40]

My Sansa Clip +'s battery was running low, so I decided to try replacing the internal battery with an external battery pack, powered by 3 AAAs. (After reading this post from a user who did it and verified that the voltage range was acceptable) It seemed to work fine for the first week and I began to see better battery life, but last night I tried swapping in some other batteries I'd just fully charged. The player still started up fine after I put them in, but this morning the player would not start. Holding the power button gets me the Rockbox startup screen with "Boot 4.0" at the top, but it turns off again as soon as I release the power button. Sometimes a message saying "ATA error: -2" appears afterward if I hold the button long enough. Something similar happens if I try booting the original firmware. The player does work normally when plugged in, and I can access the database and play files as usual. I'm guessing the voltages from the fresh AAAs were too high after all and damaged something. How salvageable does this situation sound?

(Also, I hope this is on-topic for this forum. I would post on anythingbutipod.com, but it has been having technical issues and I am unable to sign up for the forum)

[saratoga]

That link uses NiMH batteries, which are slightly lower voltage and should be about 4.2v fully charged just like a lithium ion battery.  Did you measure the voltage on the pack you're using?  The datasheet says up to 5.5v is allowed for the battery voltage, but I'm not sure that we have necessarily configured everything correctly to operate at higher voltages.

[dpitch40]

The pack currently connected measures 4.21 V. EDIT: 4.19 now. I highly doubt it could have been any more than 4.5 V when I put the charged batteries in last night, as they are fairly old.

[Mihail Zenkov]

Try connect your battery pack through usb. It will be less efficient but still should work.