Full Review - 18650 Cell Charger

More on the slightly odd 18650 cell charger bought on Aliexpress
www.aliexpress...

[@mrlithium69]

I like that you went through the detail to point to every chip, name it, model number, what it does, what path the flow is going, and explanation of why. Very good Sir !

[@JulianIlett]

Awesome, thanks :)

[@steveroberts1861]

The ability to discharge an external battery isn't such a bad idea. Those battery banks might show 15,000mA capacity but in reality you are only ever using the stepped up voltage. So to have a capacity reading post step uup converter makes sense.

[@JulianIlett]

True - you can find the actual capacity at 5 volts :)

[@restorer19]

@@JulianIlett You can find the efficiency of the boost converter by measuring the mAh it takes to fully charge the powerbank, convert that to mWh based on the battery's voltage, then measure the total mWh in discharge at ~5V, and comparing the two.

[@christopherguy1217]

The USB discharge connection is very useful if you want to measure actual available power from the bank after all losses. If I have two identical 10 AHr banks but one is 93% efficient and the other cheap Chinese one is 80% efficient I want to know that. Plus who believes the numbers written on the case?

[@pault6533]

I have the newer versions 3.0 and 4.2. They deleted the on off switch and added charger circuitry to charge the left cell. These newer versions also support installation of larger cells via a cell holder change.

[@MoisesCaster]

Hi! I bought this device. The second USB connector is for testing AC chargers, to see if the charger delivers the 1 amp needed to charge the battery.

[@flagpoleeip]

I would dispute the idea that the USB socket on the right is useless. It'll give you the actual useful capacity of the power bank! I can think of lots of reasons why you'd want to know that. Like if you've got a known load and you want to know how long it would last!!! I appreciate that this number might be disapointing but that is hardly the point.

[@tigrafrog]

@9:45 - "I can't see point of that" -- sorry, but you're very wrong. Given that powerbank output only 5V (no QC), 100% of the time for powerbank will be used with 5V. So it's absolutely valuable info for end user - how long I can use it with 5V 500 mA, 5V 1A, 5V 2A. All other info (real cells capacity) will be absolutely right and absolutely useless for real world application. For me unit with less cell capacity but with more efficient boost converter will be more valuable than larger cell capacity and less efficient boost converter. Even at the end those 2 unit will be same on output, price will be different.

[@promcfire]

The variant without an on/off switch does charge the left battery slot, so it is a lot more useful for testing batteries. You simply charge on the left and test discharge on the right. mOmh testing is consistent, but shows lower values than my opus charger, still very useful. I think mOhm testing on this unit is quite good 👍

[@MCsCreations]

Really interesting device indeed, Julian! Great review! 😊 I've just found out there's a 4 ch version as well... That one looks more interesting, with 4 independent chs and so on... Anyway, stay safe there with your family! 🖖😊

[@Beeeeeeeeeee]

For easy extraction of the cells from those holders: squeeze the spring contact a bit with pliers, it'll be not so strong and release the cell easier.

[@quandiy5164]

This. I did this to a batch of similar cell holders that I bought. The springs were so tight that the plastic breaks apart when a cell was inserted.

[@SuperBrainAK]

Keep in mind you can easily convert from 5v Ah capacity back to 3.7v Ah capacity. For example if you tested a powerbank at 5v and got 11.1Ah what you do is multiply them together to get 55.5Wh which is Watt-hours, then divide by the nominal voltage of the internal battery to get the cell's capacity in Ah @ 3.7v which is 15Ah yes you do need to factor in losses for the conversion but you can easily do that by multiplying your Wh by the percentage 80% or 90% so 55.5Wh * 0.80 would be 44.4Wh of usable capacity.

[@Brian_Of_Melbourne]

Surely, the amount of energy (Wh) that a battery (power bank) can deliver is the important information. That, after all, is what the device you are charging cares about?

[@SuperBrainAK]

@@Brian_Of_Melbourne yep, tell the industry that, it is how it was when powerbanks started, they just put what the battery manufacturer said it was so they slapped that on the box. You do often see Wh added on larger batteries and portable power stations, which is a step in the right direction.

[@GannDolph]

testing a power bank's capacity at real 5v output is useful since that's the output you actually have access to. the 15,000 number is arguably the more pointless figure no? instead of that lolly stick i use a couple loops of thin flat ribbon (from the wife's xmas present wrapping supplies) placed around the cells before insertion, to pull on to extract cell .

[@JulianIlett]

Yes true. Some of the larger power banks quote total capacity and usable capacity. Or maybe I'm thinking of EV batteries :)

[@transmitterguy478]

I just received mine and the display dimming is a pain. I you figure out how to keep it full brightness let us know. Great videos Julian!

[@cmyanmar13]

Some USB powerbanks which switch the output off under low load allow you to keep it on with a double-click or click-and-hold of their button.

[@ErrorMessageNotFound]

I test every powerbank just like this. I would argue that what you need to know about a 5v usb power bank is what it can deliver at 5v. I don't care how about the exact capacity of the cell(s), I care what I can get out of the unit. I.E. how many times can I charge my phone before the power bank goes dead. Unless you dismantle the power bank it's the only way you can test it's capacity anyway.

[@ndmusick11]

Just had an idea you put tape on each battery to make a flag it would make them a lot easier to pull out

[@MaxGoddur]

Have you ever played with ESP32-Cam boards?

[@JulianIlett]

Briefly flirted with ESP32, but it's all toolchains and software versions. It's not for me.

[@hobbyrob313]

attiny85 usb? Hello Julian? can you tell me about this please?

[@MrPir84free]

Being able to measure internal resistance is more about being able to select used or new batteries to go together in a project; Being able to put a load, on the right USB-C would be beneficial as one could see how much of a load it could take, and what sort of voltage drop one sees. If I wanted to put that contraption in a safe container, I'd use a pyrex container instead; for the heat, and safety aspects of such a device. Note: using amazon as a reference, it shows using a holder for a 21700, connected to the positive and negative wires of a usb c connector; i.e. so that one could simply use a different battery holder and type with the device. Plugged into the right USB as a "load" and just ran that way. hmmm

[@Johadart]

Hi Julian, just a quick question about this unit, I have purchased same item, but the chip is a TC4056A, could you please advise whether or not that chip is for normal 18650 LiPo batteries, as I’ve read the data sheet and I don’t quit understand it.. also the version I have doesn’t have an on/off switch... thanks Joe from Australia 🤙🏼🇦🇺

[@MaxintRD]

I have the similar version, without the on/off switch. In stead, the left button is for on/off/menu and the other two are for change and start/stop. On the location of the on/off switch my version has a second TC4056A with a traditional charging circuit including two led's, similar to the cheap TP4056 charging modules. That circuit is not controlled by the micro controller, but it merely charges the left battery when the device is plugged in. As it seems to charge the same way as the TP4056 I think the TC4056A is just a clone, similar to the TP4056, aimed at charging normal 18650 Li-ion batteries. Other than that I've read manuals that show a version with on/off switch, where the third button allows selecting a lower discharge current. Our version doesn't have such feature.

[@Johadart]

@@MaxintRD Thankyou for the input mate, I missed the second one on the Left, but sure enough it’s there, so ours do both in charging? Wow never knew that part, thanks again mate. Very helpful. 🤙🏼🇦🇺 Joe from Australia 🤙🏼🇦🇺

[@Johadart]

Oh P. S I subbed to your channel also max

[@MaxintRD]

@@Johadart Thanks for subscribing. Although I've not published new video's recently, I think the old ones could still be useful. I'm still doing electronic projects and maintaining my Arduino libraries, but couldn't reserve the time to make new video's. I still would like to make new video's though. Perhaps one day, sooner or later...

[@Johadart]

@@MaxintRD That sounds awesome mate, I’ll be checking out what you have so far. Might be a good way to get back into it. I’ll be sure to spread the word. 🤙🏼🇦🇺

[@McTroyd]

Nifty widget. Voltage / current = resistance; maybe that's how it's measuring?

[@johnarmstrong3782]

Think I'll stick to my LiitoKala...

[@andymouse]

So that's it ! the Chinese when doing there specs say " what's the point of writing a very precise number on there I'll just round it up " Lol !...cheers.

[@davidcoates4852]

"Quirky and quite frankly rather useless device." ✅👏🔧👍

[@jimquinn]

"Potential current"...........funny......

[@JulianIlett]

I also say ' the current voltage'. He he.

[@fredflintstone1]

Hmm, an over complicated simple waste of time item, I much prefer to use my opus charger does the same things but does 4 at a time

[@JulianIlett]

Yeah, that's the conclusion I came to. A purpose made charger/discharger (mine is branded Adeaska) is better suited to the job. Four slots, sliding battery contacts, proper settings for LiFePO4 etc.

[@JulianIlett]

On the other hand, I do like things like this. You can see exactly how it works without having to take a case apart :)

[@andymouse]

There you are !...Squeak!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[@fredflintstone1]

@@andymouse Cheese!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[@MaxintRD]

The version of this device that I got was less than 4 euro's. I guess your opus charger was a bit more expensive. (With only one slot testing a lot takes more time, but it's automatic mode let's me start at night and see the result in the morning. Good enough for testing only a few batteries...)