[G1 Accessories] n19htmare:
Alright so Last night I finally got the battery down to 9%. I've got some interesting findings.

Few more things I'd like to point out before presenting some numbers.

Background on battery ratings: Batteries are rated in mAH aka Milliamp Hour, or how much power/charge a battery will hold. How is this measured? I won't go into details so will just give a run down version of it. Batteries are rated from their lower cutt-off voltage to the maximum voltage. The lower cut-off voltage for Li-ion and Li-po is 3.0-3.2V (3.2V being ideal).

The mAH rating is the amount of charge that it took to take the battery from 3.2V to 4.2V. In the Li-ion case, the lower cutt-off is 3.2V, the Nominal voltage is 3.7V and the maximum voltage is 4.2. Anything under 3.2V is over draining and anything over 4.2 is overcharging.

Why do I bring up the above? to give you an idea of how these batteries get rated.

Often companies will rate their batteries from a lower cut-off point to have HIGHER CAPACITY RATING. For example, if I Charge a li-ion cell from 3.0V to 4.2V, it will take in extra capacity as opposed to if I charge it from 3.2V to 4.2v, It just looks good on paper and spec sheet. This happens often. same with AA rechargeables, the lower cutt-off range is usually 1.0V but often companies will rate from .9V to achieve higher numbers. You will never see this disclosed on the battery, you'll just see the rating. (It will never say Capacity 1800mAH from .9v) etc.

Again, what's the point? There are a couple of points.

1) The G1 NEVER drains the battery down to 3.2V. It's cut-off point is surprisingly 3.5V. I do not know the specifics, perhaps the G1 cannot operate below 3.5V.

This means that even though the phone is dead, the battery still has some juice in it, just not enough to power the G1 or it may be enough to power the G1 but the power management of G1 is not allowing it.

The stock G1 battery which is rated at 1150 mAH, is only being used down to 3.5V, which means you're only using ABOUT 800-900 mAH of it's capacity before phone shuts off.

2) This Yoobao battery is surprisingly, very well rated. At 9 % power, It was still reading 3.6V. REMEMBER: that's 9% till the 3.5V cut off. The battery was most likely rated at 2400mAH from 3.2V! When I hooked it up to my li-ion charger, I was able to push in roughly 2000mAH. so In other words I rate this battery 2000mAH from 3.6V. Yoobao rated it 2400mAH from likely 3.2V. And I would conclude that the rating is accurate and not over inflated.

CONCLUSION: You will never use the full capacity of the battery just because of the way the G1 is designed. It will always cut off at 3.5V. The good thing about this is you will never over drain your battery, so you can run your G1 to the dead point as many times as you want as you will never go below 3.5V. Nice feature but I'd rather have it go down to 3.2 so I can squeeze that extra power out of the battery (Wonder if this could be software modified).

TWO THUMBS UP!!! to YOOBAO 2400mAH battery. Priced at $25.

Some rough numbers:

Stock 1150mAH : 850-950 useable mAH

2400mAH: 2000-2100 useable mAH

2600mAH: ASSUMED 2200-2350 usebale mAH as I have not test my brothers seido yet.

Any questions, I'm happy to answer them.

*I'm in no way shape or form related to the manufacturer of any batteries, I'm just a regular consumer who bought the extended battery and decided to review it since it's rather a new product.