Top positive review
65 people found this helpful
Great for charging Smart Phone
on 21 November 2011
Bought this for charging my Samsung Galaxy S2 for whenever mains electric isn't available, especially when travelling or doing multi-day back-packing. Really pleased with the iEP390, leave it to charge up overnight (its important to leave it 8+ hours and the charging lights go out when its full (rather than unplugging it when the 3rd LED comes on as this may only be 70% full). Have charged it about 4 times so far, and each time used it to recharge my Galaxy S2; it recharges it from empty (5-10%) to full (100%) three times and only takes 3 or 4 hours; then the iEP390 can still do one more charge of to about 70%. So for my phone, recharging it with the phone switched on, but the display off, it can do about 3.75 recharges.
The iEP390 is 11,000mAh whereas the S2 is 1650mAh so 11,000 divide by 1650 would suggest it ought to do 6.5 charges but I knew it would be less than this due to some of the power is lost due to heat build up (the S2 gets mildly warm whilst being recharged) and transfer inefficiencies - and I guess that iEP390 isn't able to charge the S2 once its power level drops lower than the battery level it has built up in the S2 during the last charge (when the differential in the iEP390 is < the S2).
The iEP390 comes with a handy little cloth bag and a variety of charging tips including the one I needed for the S2 (micro USB), its just a pity that they don't include the tip for the Galaxy tab, but the Galaxy Tab's OEM USB cable should fit.
Having researched a little, the iEP390 had the best performance in terms of weight and price. It isn't light nor small, but its not too big or heavy. For my use it offers the best power:weight performance and the best power:cost value. With the iEP390 I can reasonably keep my phone charged for nearly a week between getting to a mains electricity, rather than 2 days. So really pleased, recommended but keep in mind you'll only get about 60% of the number of charges you might expect.