XPS M2010 Keyboard battery hack... help?

Hi, I recently bought an XPS M2010 keyoard on ebay without the battery. I want to use it with my PC with already has Bluetooth. I didn't realise it used a "special" Dell battery though, I thought would use regular AA.

Rather than buy a very expensive Dell battery, and still have now way to charge it, I want to power the keyboard with regular batteries. As an engineer, I can build what I need and such, but I don't know what the power requirments are for this keyboard. 

After opening the keyboard, I see that there are 9 wires that go from the battery connector to the PCB board in the keyboard.  It looks like all of them are being used on the board, but I assume that a few are being used a status and communicating back to the XPS system. 

I just need to know what the volage requirements are for this board/keyboard and which pins they apply to.

I've search online for pinouts and schematics but found nothing.

Can anyone help me out?  Dell?  Public?

thanks!