Anyone have any opinion if this 2900mAh battery would last longer?

Caught this on eBay. A 2900mAh battery. Isn't the OEM a 2100mAh? Does that mean the eBay one is likely to last longer? (assuming it lives up to what it's being advertised as)

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Thanks for your info!

IF it really provides 2900 mAh capacity, then yes.

But think about it: Chemistry is chemistry. A single Li cell of a given size has a given amount of capacity. The only way to increase that capacity is to make the cell bigger, or wire multiple cells together. Or both. Given that this battery is the same size as OEM, how exactly did they cram 38% more cells, or 38% bigger cells, into that space? And do so at a cost of only $5 per battery?

I've bought cheap Chinese 3rd party batteries for several devices simply because they're cheap. In pretty much every case, regardless of the claimed capacity, in real use they discharge faster than the OEM battery, and fail to hold a charge after 12-18 months. I use them as backup batteries, if I need to swap part way through the day, and at a price of $5 a battery it's a worthwhile trade-off for me. But I'd take any capacity claims with a very large grain of salt.

If it sounds too good to be true......

Ahhh... dreams shattered. But, you are probably right. :)

Funny cause a few months back I bought this EXACT same thing.... 2 "2900" mAh batteries plus a wall charger for 10 bucks. They really are NOT 2900 and in reality they last way LESS longer than the OEM battery the phone came with. Ended up selling both batteries back on eBay (for $10 each, so I made $10 lol) and bought the Hyperion 4200mAh battery. Now I get 50hrs per charge.