I have been a fly on this wall for long enough. I am enjoying this thread a lot and thought I would put in my 2 cents.
I decided to look into other battery related articles written by Hannah Francis, and found one here:
http://www.smh.com.au/digital-life/digital-life-news/this-yoke-and-shell-battery-could-charge-your-phone-in-six-minutes-20150811-gix2vz#comments
It is about battery technology that could allow an iPhone battery to be fully charged within 6 minutes. Theory is nice, but ZERO math was applied to this article. The last person to comment on the article did some REAL math revealing the current involved in charging a battery that fast. It may be possible, but far from practical.
And a reminder to batteriser...
![](http://wattsupwiththat.files.wordpress.com/2012/07/scotty1.jpg)
My concern with comment is not the math, they seems to be fine for me, but where does the "4 times 2500 mAh battery" come from?
And why speaking about 4 AA battery? this article is about charging a SMARTPHONE battery in 6 min, not replacing a NiMH battery, nor 4.
Based on Hannah's writing style of the above linked article, I would expect her to side with new technology along with little technical fact checking (if any). Also he made assumption that these battery will have a nominal voltage of 1.5V, but nothing tell that.
For example my iPhone 5s have a 5.92 Whr (1560 mAh) LiPo battery so the nominal voltage is 3.7V.
So taking the same calculation as him:
The battery is 1.56 Ah, T still be 6min, so 0.1h
I = C / T = 1.56 / 0.1 = 15.6 A + 10% = 15.6 * 1.10 = 17.16A (not sure about that, the main goal of this article and type of batterie is that the charging efficiency is really high, 10% of loss is quite high for me)
So for the 240VAC vs DC output, 3.7/240 * 17.16 = 0.26A or mure accurately, charging such a battery in 6min would need a 60W charger (or approaching).
But that's normal that quick charge need more power. But such a battery will also mean that in the same conditions as it is currently the charge your battery will be much quicker.
I've search with my friend google, and a LiPo charging efficiency seems to be about 60 to 70%
NiMH seems to be about 85%.
So I suspect that such batteries would be higher than 90%.
Anyway, even a 90% efficiency against a 60% efficiency is about a 50% improvement in charge speed.
(and sorry if I say something stupid, my head hurts today)