Hyperion AT&T Samsung Galaxy S II 4G 2 x Battery + Charger
Just ordered at Amazon for $25. Batteries are 1800mah. Not many reviews but all are saying that there are NO boot loops and that they work with original back cover. My guess is that these are NOT NFC batteries. They should last at least as original battery. I'll update post when I find out.
I tested my Hyperion batteries and they have about 5% LESS juice compared to stock battery. Another gripe is that charger output is rated as DC 4.2V 350mA (but mostly performs well below) so because of that, in my case, it takes 6+ hours to fully charge completely discharged battery. Some people reported 4 hours to fully charged state so each to it's own. If you charge phone thru charger's USB output you'll get full 750mA charge.
Anyway, considering all positives, negatives and price, I'm satisfied with this purchase and this is viable option for I777.
- no boot loops
- same form factor
- charger charge stock battery as well
- price (2 batteries and charger $25)
- extra USB output outlet (750-800mA)
- batteries hold close to stock (it was expected knowing that weigh and size of batteries don't differ much compered to stock)
- not NFC compatible (not much of use for NFC right now)
- slow battery charging (~350mA)
- batteries hold ~12% less then advertised (~5% less then stock battery)
- once it gets below 20% it drains faster. Especially true for last 10%.
Maybe it'll get better over time. If someone found a way to properly calibrate this battery to show full potential, don't be shy, let us know.
See post #14!