@flaschus Huh yeah I guess voltage spikes like @feha said. I dunno. Again I am the farthest thing from an electrician. I just have wired up some RC stuff in the past. Did the camera die right on a fresh battery? Because the lipos usually have higher voltage when just charged then settle down after a little bit.

@flascgus Looks like you have the right voltage. Nimh or Nicad are 1.2v/cell and you have 7 there, making 8.4v. The only thing I can think of is if it was reversed polarity. Did you check it with a meter?

I've built these before and always use the Castle Creations 20a bec. Had one plugged into the wall (via wall wart 12 v AC-DC converter) for 3-4 weeks straight doing timelapse shots. They also work well from any battery with a voltage above the target voltage. You do have to have a little usb device to set the voltage though. (castle link software for PC only)

Caution should be taken with Lipos. They have been known to burn houses down. If you accidentally puncture it, it will pretty much become a fireball. Same thing if you charge it the wrong way. You need a balance charger. Care also needs to be taken to not discharge them below 80% of their mAh capacity, or about 3.8v per cell or they will have a very short life.
For this application it would be good to get ones that come in a hard case, meant for RC cars.

@feha thanks for getting the tutorial sorted :)

@chrimsbroome

The list of links is on youtube video description ... The cost depends from what components you want to buy ... minimum: Step Up Step Down Voltage Module - about 8 GBP , 10pcs 5.5mm X 2.5mm DC Power Supply Metal Jack Socket - about 10 GBP and some wires , the alu box - about 12 GBP For the more advanced version the cost is a bit more, but still affordable ...

Just received my 9v UBEC and wired it up. I have a voltage display somewhere I have to wire in but the UBEC puts out a super stable 9v and the camera works perfectly.

Would this battery be a good possibility? I like the size...

http://www.ebay.com/itm/6400mAh-Rechargeable-8-4V-Battery-P7-XM-L-T6-LED-Bicycle-bike-HeadLight-Headlamp-/250907264154?_trksid=p4340.m185&_trkparms=algo%3DSIC.NPJS%26its%3DI%252BC%26itu%3DUA%26otn%3D5%26pmod%3D170710221252%26ps%3D63%26clkid%3D7690970456910103103#ht_4297wt_952

Ran that setup today for about 3 hours. Worked well but the only thing that was interesting was that if the battery was plugged in but the camera not on the UBEC got pretty warm. So I am thinking it needs a switch or something to keep current from the UBEC when the camera is off but the battery is plugged it.

It doesn't suck that it has or can have the little velcro bag ...might be good for putting on the rods.

@feha , thanks for the tip!

So shall we dismiss such alluring battery pack?

But if I want to use the 8.4v 6400 mA battery and the 3.5-28V to 1.25-26V DC-DC Converter Boost Buck Step Up Step Down Voltage Module, shouldn't such module guarantee that the voltage does NOT drop?

Well I took the plunge and ordered both. It'll take almost a month to get them, but I'll report as soon as I test them.

@NURBS Nice setup. What cage arm is that? And where did you get the battery? When I bought my Lilliput, it came with a smaller battery, which didn't have any 1/8" mounting options.