Funny you mention this! I recently ordered a supposed 50,000mah USB battery from ebay for my 2nd 70d! As usual, too good to be true! I'll NEVER buy batteries OR sd cards from ebay EVER again! I'll just stick with Amazon for stuff like that! Well anyway, I was HOPING that I got at least 30+ hours with this CLAIMED 50,000mah battery. In reality, I'm getting 5 hours reliably from this battery
Which leads me to believe that its REALLY a 5,000mah battery and NOT a 50,000mah battery
They just slapped an extra 0 onto the battery and claim its that high of a capacity! Now I realize that I only paid $12 for my battery[same as Voltronic] and I am certain that its not an authentic battery, or they just flat out lied about the capacity! I just sent a return request and I'm going to try to exchange the battery hoping that I got a dud, but I'm sure its going to be the same damn thing with the exchange
My 70d draws about 1a/hour[4 channels@24/96 with MK4 Phantom on 1/2 and LINE on 3/4], so a 50,000mah battery SHOULD last me about 50 hours, that's why I'm about 99% certain that its just a 5,000mah battery, since I'm only getting 5 hours! All Im saying is, Just be cautious of where you're buying, and avoid ebay for sd cards AND batteries IMO! As always, YMMV!