Quantum Turbo 2x2 Battery Replacement

[ben_hutcherson]

I've replaced my fair share of batteries in Quantum packs of different generations, but this one has me stumped and I'm wondering if anyone can offer any insight.

The 2x2 uses 4/5 Sub C NiMH cells. I don't actually know how many, but I have plenty on hand to do it(I ended up buying 25). If I had to guess it's either 7 or 8 but don't actually know(the original Turbo uses an 8V battery...).

In any case, it's easy enough to pull the "brains" out, but I'm stuck with actually getting the cells out of the case. It uses the same style leatherette type case as the QB1/2/Turbo, although a different size and shape. It seems as though Quantum used a double sized foam tape to secure the pack to the case.

I've gone in with a knife and thin straight edge to cut the 4 strips of tape I've found, and have twisted and otherwise manipulated the case any way I can think of. There's no way to get a good hold on the battery pack that I can see short of yanking on the wires, and no amount of shaking or anything else seems to even get the battery pack to want to budge.

Has anyone done one of these before themselves?

BTW, I'm not a stranger to re-celling in general and once I can get the pack out and use it as a template I'm equipped to "do it right". I have a spot welder, a selection of nickel strips to weld the batteries together, and plenty of shrink wrap for battery packs in different sizes. I just need to get the pack out!

[ben_hutcherson]

I thought I'd follow up on this one-

After doing a bunch of hunting, I finally found a suggestion on a different site where someone discussed using a butter knife to work the pack out. I was able to get it out doing this.

I finally was able to finish this one up the other night-it bench tested fine although I've not actually reassembled yet. That part's not complicated. I'm reluctant to tape the replacement back in like the original, but the original also had some adhesive foam rubber around the edges of the pack and I'll likely test fit and add some of that to at least give some security.

Not the best photo, but taken on my work bench at around 11:00PM after I'd finally finished everything up and was test charging. The original pack is to the right-my new/rebuilt one is in the blue shrink wrap

This one was a bit of a fun challenge. A flat 12 cell pack in a 4x3 grid is easy enough to build, especially after I upgraded my battery spot welder. The really cheap Amazon ones can work, but don't give particularly consistent or pretty welds. I bought a "Glitter" brand 801 series spot welder, another Chinese special but a somewhat higher end model. This one uses a big supercapacitor to make the welds(reading the directions helps-I thought at first it was bad, but when new it just needs ~30 minutes to charge up the capacitor from the tiny little wall wart, but once charged it can make a LOT of welds without draining it down too much and needing a break to recover-I have yet to have to build an intentional pause into a work section). 

As to this battery pack, though-this is not unusual for NiMH packs, but there were a few temperature sensors that needed to be extracted from the old and transferred to the new. I mangled the original battery pack to board plug trying to get the old pack out. It's a JIS 2.5mm connector, so I just opted to replace it completely. That involved a crash course in learning to crimp these, which isn't complicated. The original pack seemed to use a mix of 28AWG and 24AWG wires-I did the new in all 24AWG since, why not? Quantum apparently saw fit to double up the actual power carrying wires(two positive and two negative-the green and white wires are to temp sensors) so if they thought 2x28AWG was good, and 24AWG will both crimp properly into the connectors and fit fine in the same application, I don't see any downside to using the heavier wire.