AA Li-Ion battery charged with USB-C

Is the output voltage cut off automatically after discharge, without warning or lowering the output voltage beforehand?

These types of AA sticks are advertised as follows:

Which suggests keeping the voltage at 1.5V for cut-off.
The 100% charge signal is only visible when 5V is connected via USB, then the indicator light is on continuously.
Charging is indicated by slow flashing.
In my case, the light flashed very quickly - this condition is not described on the packaging, but it signals a cell failure - open circuit.

Measurements have shown that below the voltage of 3.15V on the cell, the output voltage is suddenly reduced to 1.1V. The power supply is cut off at 2.8V on the cell.


When charging at the output instead 1.5V Is 5V , which makes it impossible to charge and use the "battery" at the same time.
When you think about it, from the electronic point of view, it is closer to a power bank than to an AA battery, with the difference that it does not increase the voltage from 3.6V to 5V, but lowers it to 1.5V.

Is the output voltage cut off automatically after discharge, without warning or lowering the output voltage beforehand?

I`ve written this before, but I`ll say it again:
In the cell voltage range of 4.20 V ... 3.15 V, the converter output is 1.51 V
In the cell voltage range of 3.14 V ... 2.80 V, the converter output is 1.10 V
Below the voltage of 2.80 V on the cell, the converter output is 0 V

The battery with the converter and charger is a power bank.
The cell mentioned in the description is a secondary electrochemical cell - a battery.
Nice for powering something from one battery. Once discharged, it can be removed and charged. 5V into a device designed to be powered by 1.5V may end badly for the device with this powerbank.
Using 4 pieces in a camera or blood pressure monitor is a pain, because you have to connect them to the power supply one by one, or have several power supplies, or have a power supply with several USB ports and several cables. If someone likes it, why not? In terms of volume, the solution is quite similar to a charger with 4 sockets and a mains adapter. And you can borrow a power supply from someone, because now everyone has one, and often more than one.

There are cables available with several USB-C outputs https://www.amazon.com/GELRHONR-Splitter-Char...ble-%EF%BC%884FT-1-25M%EF%BC%89/dp/B08GY7FBHZ so if anyone he often wanted to use it, there is no problem with charging.

The set includes a cable with a branch for 2 pcs.

These branched cables are dangerous in certain cases. When connecting one output to a device with the fast charging protocol, a voltage higher than 5 V will appear on all terminals. Not every device with a USB connector will withstand higher voltage. You need to be careful.

https://www.usb.org/usb-charger-pd

The cable must also support PD, so if they didn`t mix it up, there shouldn`t be a problem.

Older protocols, e.g. Qualcomm Quick Charge 2.0, do not pay attention to the cable type.
https://blog.oxplot.com/quickcharge/
https://en.wikipedia.org/wiki/Quick_Charge

Thanks, they actually figured it out cleverly. Maybe someone with an electrode will be tempted to open such a splitter. Maybe there`s some security inside.

mipix wrote:

I`ve written this before, but I`ll say it again:
In the cell voltage range of 4.20 V ... 3.15 V, the converter output is 1.51 V
In the cell voltage range of 3.14 V ... 2.80 V, the converter output is 1.10 V
Below the voltage of 2.80 V on the cell, the converter output is 0 V

Thanks!
I have something like this, only in the R20 version in a gas heater, just yesterday
the diode in the stove started flashing, indicating that the power supply voltage was too low.
This surprised me because I thought it would work until it completely failed.
This is how a toothbrush works, it turns off without warning.

They are not universal, but they are certainly perfect for what kucy7 writes. If there was no demand, there would be no supply.

Out of curiosity, I searched a bit on Aliexpress and there are those with a capacity of 600 mA (max 2000 mA).


There are also versions without a charging port. These must have a special charger.

Demand/supply - this is simple manipulation. The manufacturer forces people to buy a product with a lower capacity than alkaline cells or NiMH batteries. It also has a shorter lifespan than NiMH, so only fashion should make a person buy it. And if fashion controls someone`s life, let them spend money on low-quality, but fashionable goods. In my opinion, the Chinese are trying to take over the alkaline cell market and perhaps they will succeed with the help of housewives and the EU, which forced the standardization of power sockets. Now everyone has the so-called charger, so there is nothing stopping you from using these substitutes for alkaline cells or NiMH batteries.

When it comes to capacity, it`s not entirely true. Approximate capacity in size AA


As for durability, time will tell. As you can see in the first message, it is different, because the cell with a production date of December 2023 (a month old) had a defect. Nevertheless, I ordered 2 pieces of the cheapest ones for testing in the wall clock. According to the buyers` description, they have about 700 mAh instead of 2600 mAh, but otherwise it was impossible to buy converters from 3.7V to 1.5V. Currently this is the only source. Ultimately, they will be connected to 18650 cells.


I also use a 9V substitute in a multimeter. An interesting fact is that on a regular battery or NiMH accumulator, the meter works normally, but on the Chinese invention it makes a squeaking sound. It`s the fault of the converter in the battery. Declared capacity taken from the ceiling.


There are also those that promise not to "noise", but I`m not going to test it.

The average user doesn`t want to bother with charging. The charger is a big expense and you have to think about it. These products are targeted at such users - they already have chargers, they won`t think about it, and they won`t be able to count any profits or losses. Why does your neighbor buy such expensive sticks when you can buy cheap ones? And he doesn`t know that cheap ones last half as long. It wastes time shopping and exchanging and produces a mountain of waste.
This is also an example of littering - in every "power bank", a substitute for a dry cell, there is a converter and a charger, i.e. additional electronic waste. Lithium-ion batteries have a service life (number of complete discharge/charge cycles) lower than NiMH. The only advantage is higher energy density, but it is invisible here, because there are converters and chargers instead of a battery, possibly at the expense of the battery capacity.
A plus for signaling the low state with low voltage, thanks to which the powered device shows that it is time to charge.
I still think it`s more of an attempt to take over part of the market than any benefit to the consumer. The role of the consumer is to consume and let him decide what he wants to consume and for how much.

I read opinions about these batteries and it looks very bad
https://allegro.pl/oferta/akumulator-xtar-14500-1-5v-3300mwh-li-ion-4-szt-14508559254
https://allegro.pl/oferta/kp-icr14500-226pcm-2260mah-li-ion-m-usb-1-5v-14329040850

Usually, such batteries in remote controls come in pairs. Why didn`t anyone come up with the idea of having only one 3V battery + a jumper battery?

What problem would such a battery solve?

1. Converter from 3.7 to 3, not 1.5V
2. Only one battery to charge
3. Charging without removing the battery from the remote control (only the cover removed)

LEDówki wrote:

(...) Lithium-ion batteries have a service life (number of full discharge/charge cycles) lower than NiMH. The only advantage is higher energy density, but it is invisible here, because there are converters and chargers instead of a battery, possibly at the expense of the battery capacity.
(...)

In my opinion, the biggest advantage is the lack of memory and the ability to recharge at any time.

bsw wrote:

1. Converter from 3.7 to 3, not 1.5V
2. Only one battery to charge
3. Charging without removing the battery from the remote control (only the cover removed)

I took the easy way and used one cell with a !N4148 diode in series with the ZY_TH1 temperature sensor Tuya WiFi every 2 AAA batteries milked in about 3 weeks.
Now I have a 3.7V 3500mAh cell and it has been working for 8 months.

I power the Sony UCT-042 TV remote control directly from a 600mAh cell, probably from a Nokia 3310. There, it charges the cell to 3.6V and lasts about 4 months without charging.

LEDówki wrote:

perhaps he will succeed with the help of housewives and the European Union, which forced the standardization of power sockets. Now everyone has the so-called charger, so there is nothing stopping you from using these substitutes for alkaline cells or NiMH batteries.

After all, these cells have been on Ali for years! What Union and conspiracy again?
The second thing is that the solution is very good, even for devices that can only handle 1.2V batteries on average. E.g. old mice. I have one myself and the battery is OK, but the battery life is very short, the voltage drops to the nominal value and that`s it. Such a combined cell would work well in such solutions, in all those that are power-hungry and this cell will cope and require quite high voltage for a finger.

Added after 4 [minutes]:

bsw wrote:

Usually, such batteries in remote controls come in pairs. Why didn`t anyone come up with the idea of having only one 3V battery + a jumper battery?

Oh my, what a saving. My TV remote has been working on batteries for... 6 years? At least, what`s the point of using batteries, let alone such inventions?

Added after 7 [minutes]:

Jacek Rutkowski wrote:

I power the Sony UCT-042 TV remote control directly from a 600mAh cell, probably from a Nokia 3310. There, it charges the cell to 3.6V and lasts about 4 months without charging.

What is this modification for? Because for this purpose, I wouldn`t want to remove the flap from the remote control Not to mention soldering something etc. And if you put in regular alkaline batteries, after a few years you might forget what type of cells are there
So, every 4 months you load your invention. And now think about it, you`re not at home, you were run over by a bus, you were eaten by a wild boar in the forest... and your family threw away the remote control because there are some strange batteries in there.
Standard solutions have a lower price and are usually less annoying

Jawi_P wrote:

Jacek Rutkowski wrote:

I power the Sony UCT-042 TV remote control directly from a 600mAh cell, probably from a Nokia 3310. There, it charges the cell to 3.6V and lasts about 4 months without charging.

What is this modification for? Because for this purpose, I wouldn`t want to remove the cover from the remote control, not to mention soldering something etc. And if you put in regular alkaline batteries, after a few years you might forget what type of cells are there
So, every 4 months you load your invention. And now think about it, you`re not at home, you were run over by a bus, you were eaten by a wild boar in the forest... and your family threw away the remote control because there are some strange batteries in it.
Standard solutions have a lower price and are usually less annoying

Apparently you don`t use the remote control much - or my remote control is terribly power-hungry :)

Seriously, I currently have a 4-year-old at home who, when he comes back from kindergarten, likes playing with small cars and often uses remote controls as bridges. He probably presses it every time and transmits for several hours at a time. Previously, I had to replace the AAA batteries every few weeks, and now when it doesn`t work, I use the power supply set to 3.6V 500mA and after about 1-1.5 hours I have a charged battery. During this time, my son operates the buttons because they are on the side of the screen and he can reach them
Earlier, the daughter from 2012 was bothering the remote controls...

Besides, my TV remote controls last less than 3 years and that`s because they broke and now it`s the 4th or 5th remote control because the TV is from 2011 and SONY KDL 40CX420 and I`m waiting for the fluorescent lamps/LEDs to die.

Theoretically, the symbol means a TV with CFL, and when I bought it it was described as LED. It consumes about 45W during operation and unmeasurable power in standby, so I`m calmly waiting for it to die to check what`s inside.

I happened upon a long-lived one

I have a new cell straight from Ali. A customs fee has been added to the shipment, to be paid upon receipt at the post office. As a result, the package stayed there for about a week. Delivery time equal to one month. Final price 1 pc. it`s PLN 13.50.


The manufacturer did not provide the output current.
I discharged it with a flashlight to cut off the power to the cell electronics.
Charging via USB with 5V is 670mAh. (670mAh × 5V)/1000 = 3.35Wh. Here it is about 2233mAh after conversion to 1.5V.

An AA alkaline cell is approximately 3.75Wh, which corresponds to 2500mAh.

I`m not sure if I calculated the capacity correctly.

mipix wrote:

[img-1]

Is this result for charging from 5V?
5V*0.67Ah=3.35Wh

3.35Wh/1.5V=2.3Ah
If so, it is quite possible to recover approximately 1800-2000mA at 1.5V, because the converter reduces the voltage impulsively when charging, but does not emit heat, and then reduces it again in impulses from 3-4V, so it had to be checked at 1.5V how much current it will give...

Do you see what the catch is?

Yes. Unfortunately, my charger with a discharge and measurement function does not respond to this invention.

mipix wrote:

Yes. Unfortunately, my charger with a discharge and measurement function does not respond to this invention.

This converter gives a stable 1.5V until the very end. Connect a 10R 0.5W resistor and you will have 150mA power consumption.
after 10 hours, measure the voltage, it will be 1500mAh and after 14 hours 1900mAh.

Unless you have a watch with a 1.5V battery, connect it
you will see when it stops and its power consumption is negligible compared to 150mA