Can I confirm that @fatpig battery can poewr all 3 outputs at the same time ?
As you can see, here many people used similar batteries for long.
Perhaps you could cable tie the batterry to this
http://www.ebay.com.au/itm/170867959814?ssPageName=STRK:MEWNX:IT
@Vajk Are you personally selling the battery or did you purchase it somewhere? Any clue on the duration of the external battery while filming with the GH2?
EDIT: Sorry bro, didn't see the first few seconds.
For anyone who's interested here's the links for the coupler and the battery on Amazon:
8500mAh External battery ($54.99): http://www.amazon.com/Portable-6500mAh-Rechargeable-Li-ion-Battery/dp/B007AYP7Y8/ref=sr_1_fkmr2_2?ie=UTF8&qid=1342704080&sr=8-2-fkmr2&keywords=8500mAh+external+battery+for+GH2
Panasonic DMW-DCC8 DC Coupler ($17.95): http://www.amazon.com/Panasonic-DMW-DCC8-Coupler-DMC-GH2-GF2/dp/B004OZQIGW/ref=sr_1_fkmr0_2?ie=UTF8&qid=1342704080&sr=8-2-fkmr0&keywords=8500mAh+external+battery+for+GH2
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