USB Charging made easier...
On a whim, I picked up a USB charging adapter for a Samsung P1000 Galaxy Tab and tried it with my Nook HD. It allows my Nook HD to charge from USB batteries that it refused to acknowledge previously.
The adapter is basically a USB Plug/Socket with a couple of resistors on the inside to emulate the correct voltages on the D+/D- lines. When in use, the Nook HD sees my batteries as AC input. I picked mine up on eBay for around $5 from a seller in CA. DealExtreme has one that is slightly different but should work the same. dx.com/p/usb-2-0-male-to-female-extension-cable-w-data-charger-switch-for-samsung-p7510-more-black-258964
Here is the listing on eBay for the one that I bought. ebay.com/itm/190702898352?ssPageName=STRK:MEWNX:IT&_trksid=p398 4.m1497.l2649
This will possibly help many like myself who have batteries already that the Nook HD/HD+ just doesn't like.
Hope it helps!!