Which charger has the best powerbank function's conversion efficiency rate?

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Blggg
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Which charger has the best powerbank function's conversion efficiency rate?

I am looking for a portable charger (just 1 or 2 bays) that has the best powerbank conversion efficiency rate. It doesn’t have to have a quick usb output rate like 2A+ or something of that sort because as what I have experienced, the slower the charge rate is, the more energy you’re going to get to your phone.

Of all chargers that I’ve come across, Nitecore F2 (with just 1 cell inserted) and Liitokala-Lii100 seem to be the most efficient as I got around 60-61% in average out of the total cell capacity (just would like to make the calculation simple by dividing mAh discharged by total cell capacity).

I’m not certain which charger of the 2 is more efficient as I have given away the Lii100, but as far as I remember, the Lii100 seems to be a tad better (1 or 2% better).

The Xtar PB2 seems to be a solid contender, but it accommodates just unprotected 18650s, so I’m not going to count it in.

Which charger is the best that you have come across?

mrheosuper
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Quote:
just would like to make the calculation simple by dividing mAh discharged by total cell capacity

this is wrong, you can only use it if the voltage output is the same as voltage input, which is not this case

the input voltage is from 4.2 to 3V, and the output is 5V in this case. the efficiency is much higher than your 61%

Forgot my pen

Blggg
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Thanks for correcting. I know that’s not right, but I just wanted to give an easy example of much I got so those who have observed how their chargers perform don’t have to do much of the mathematics in order to compare it. If I calculate the right way, it’s going to be about 82-84%.

d_t_a
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Interested to find the answer to this too.

Blggg
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The thread seems a bit quiet. I guess we can infer that not that many people are interested in how the efficiency goes.

I Just would like to give you a bit more info. I’ve tried reading-through HJK’s reviews and found that the Xtar VP2 was probably the most efficient I could find on the market. However, after having it myself, I found that it doesn’t have overload protection and the charger ended up charging my phone at about 1.8A on average, which makes the efficiency even worse than the Nitecore F2s and Lii100s. The efficiency is around 58% (again, with an incorrect calculation method).

If I have to judge right now, I would say that the Xtar PB2 possibly gives you the highest efficiency (according to Mr Baz’s review, he got around 62-63%). Sadly I don’t have the charger itself to test.

bmengineer
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The problem is there’s too many variables. Testing the same charger with different rates will give a different efficiency. Cells can affect this too.

Find all my reviews of flashlights and more gear at www.bmengineer.com

Blggg
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I would like to get the highest efficiency rate possible, but when charging the phone, I can’t control the rate, so this is purely based on what it does just when plugging it with the phone. How can you control it?

EDCba
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You can control it a bit, by tricking the phone into what kind of charger it is – 0.5A, 1A etc. The phone should respect that and only charge at the declared current.

There are adaptors to do this, but most are 1A or more. eg look for PortaPow and Pisen USB booster. For 0.5A maybe you can pose as a computer.

EDCba
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There are schematics for Apple 0.5A charging protocol USB connections, but you’ll have to DIY.