Now the mod plan: I will leave the original circuit alone so all the USB charge/convert functions remain the same, it will still function as a USB power pack. For the 001/002 power needs, I will tap the 3.7V power directly from the battery, go through a separate Li-ion protection board and pipe it out through a power pigtail. That way the power at the plug is pure DC directly from battery terminals.
A protection board is necessary as it protects the cell from over/under voltage and short. They are widely available, for about $2. They usually come with a technical sheet with installation info.
Cell capacity upgrade: available space in the case is 75mm x 65mm x 12mm, looks like a 5000mAH or two 2000mAH (4000mAH total) can fit in nicely. There will be enough space for the protection board. Or you can also add two more 1350AH cells and make it 5400mAH total (say, if you are modding two of these packs, then you can put all four 1350mah cells into one pack and put a 5000mAH cell into the other)
Anyway, I have no urge to upgrade the cell capacity yet, so the mod shown below is still with the original 2x1350 cell.
First,. disconnect the battery wires and dismounted one of the USB socket (there really is no need for two USB socket). I chose the 500mA one. Pulled out all the contacts, enlarge the holes in the white plastic block with a 1/8" bit.
Reinstall the now non-functional USB socket, feed a short power pigtail through it (feed through the slot in the case first.... guess how I know) and connect the wires according to the info sheet that comes with the little protection board. Leave one battery wire unconnected.
Mount the PCB back into the case, and solder the remaining battery wire. Cover the little protection board with heat shrink.
Reinstall the cover. The 2700mAH capacity is enough for me for now. Might upgrade to larger cells only if the need rises.
Final thoughts..... was this $15 USB pack a bad buy? Well, despite the shameless false advertisement (2700mah labeled as 5000mAH ), the circuit itself functions properly, it comes with a nice assortment of tips, the plastic case is easy to open and it is the proper size for the 002. The circuit board is easy to solder to and there is plenty of room inside the case for cell upgrades. I'd say it is a great starting point for a 002 power pack, heck I can't even buy a USB-->Li-ion charger board for $15 shipped, let alone the case and battery cells.
Upgrade the cells for another $25 then you will have a true 5000mAH power pack for...Everything.
Edited by AudioCats - 3/30/13 at 6:08pm