Just an update if anyone even cares :) just spent the second half of a shoot day using the ATC. Probably shooting 5.5-6 hours and the battery indicator is down to 50%. Not too damn bad!

Hmm, it's been removed from Amazon. I can't find it anymore but its a large battery for laptops and phones. I believe someone has a link in this thread before. It's completely gone now!

Also check these.

http://www.ebay.com/sch/i.html?_odkw=18000mAh+Universal&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313&_nkw=18000mAh+Universal+External&_sacat=0

@vicharris same thing but $20 cheaper...

@fredfred27 maybe they sent you mine too.. still waiting! not a bad kicker though :)

When battery packs do not charge, it can be that the charger does not recognize the battery because of lower voltage level than the charger expects, a voltage level which might still not be too low to destroy the battery. Had this problem with these cheap packs like this one:

http://www.ebay.com/itm/NEW-12V-9800mAh-Super-Polymer-Rechargeable-Lithium-ion-Battery-/140825469787?pt=Batteries_Chargers&hash=item20c9da235b

The ones I had had a chrger supplied. But it a) did only rate 12V b) it´s primary curcuit transistor simply exploded after 30 seconds. 4 batteries, 4 times a bang

So I bought some laptop chargers to charge the batteries. Those chargers also 12,6V, now fitting the voltage of the batteries. But when voltage drops under 11.8V, after filming (which is still more than harmful discharge) the chargers do not recognize the battery any more. Workaround is to connect two batteries to the charger, one with a level over 12V . Now the charger will charge. This workaround should be harmless because I guess the batteries do some natural balancing during the charge and will both end up with - in my case -12.6V. Still test this workaround in a safe environment on your own risk. Had two batteries hooked to a charger several times over night. No heat, so sign of stressed electronics. Still I worry about the day I will take a plane, because batteries with such big capacity are not allowed on board (But, ironically are present in any passengers laptop) BTW I use 12V connected to a 9V voltage regulator on the GH2

!fredfred27 Ahhhhhh. Ok. One more question. Why on earth would you need 6 of these!!!!!!!!!!!!!!! Ok, that ones was a joke :) I have two GH2s now and was thinking of grabbing another too but I have a shitload of reg batteries now too.

how about this

http://www.ebay.com/itm/Catclaw-DSLR-Rig-BP-Battery-V-Mount-Pinch-Combo-Power-Supply-For-Canon-5D2-60D-/251046499985?pt=LH_DefaultDomain_0&hash=item3a73899691

I want to make a DC coupler for 9V power supply out of a Chinese battery. I dismantled one, there is some circuitry. Is it enough to disconnect the power cells and solder proper wires to B+ B- points marked on the board?

I don't know if this has been posted yet..

Could it be that he didn't use any step downs for this, just straight up from Juice to GH2? 3 Hours seems ok

@vicharris can't find ATC on eBay...link pls :)

@Riker Found this! A little more but same thing, but black! Which is cooler :) http://www.amazon.com/Naztech-PB15000-Universal-Charger-Extended/dp/B007URKIGC/ref=pd_sim_sbs_e_5

@vicharris thanks!

@zsero and vicharris, 9V shouldn't be of any problems to GH2, correct? What would be the estimated runtime of GH2 recording with this Anker baby?

Does Anker have some sort of battery indicator?