How does a 1.5V Rechargeable Lithium-Ion Battery Work? Review/Teardown of an XTAR 2500 Battery

Why do I want to watch a video about testing a battery ? Because this is not just a battery ! 😉 As a beginner I have just learned sooooo much about these lithium batteries. 👏 Thank you so much for explaining the details in such a calm and informative style. I will never just pass on a 'simple battery review' again. Brilliant 😁

You covered under "switching noise" the problem I had trying to use Li-Ion rechargeable AA batteries in an AM/FM radio. If you take a li ion AA battery and place it close to the ferrite AM internal antenna of a radio, it completely blocks AM reception. How that was explained to me was the stepdown circuitry is working all the time whether the battery is being used or not. Your video is the first to explain this! Thank you. Great video.

Kerry, I think for a lot of applications the 1MHz switching noise will not be appearent in application. What interests me most about these are 3 things: Capacity, self discharge and chemical leakage. Since no manufacturer on the planet makes a leak proof alkaline battery (and Duracell is the worst for this as well as Costco) these batteries seem a very viable alternative. I have not researched the cost but if they are comparable to the Eveready Ultimate Lithium AA cells they are worth a look for me. These are the only cells I am currently using in my T&M equipment after alkalines destroyed the AA battery pack in my Fluke 289 DMM which cost me $80.00 for a new back. I would be interested to find out what the real self discharge looks like. It seems with NiMh cells and even some T&M gear (my Owon SDS6062 LiOn powered DSO an an example) are always dead when I need them. Thanks again for doing the review on these as I will be checking them out just as soon as I click the comment button. Sam W3OHM

Thanks Kerry. Interesting cells. But obviously RF noisy, and expensive, suitable only for very limited applications.

Thanks for explaining this. I was wondering how they work.

Great review, and an interesting cell....cheers.

It would be nice if the DC voltage conversion would work both ways, so you can charge them with a regular 1.5 volt NiMH battery charger.

Hi Kerry, thank toy for a very interesting Video, you confirmed what I thought the construction was inside the cell. Here in Sweden I bought a similar product with the brand name XOXOPO, the AA cells are rated at 1850 mAhr together with a charger that is driven by a 5V USB cable. The instructions specifically say do not use the charger for any other cell type (such as NiMH). I am using the cells for driving an electric toothbrush, so the regulator noise does not bother its operation, at least I get 1.5 V which works great, as compared with when you use NiMN cells which have an output voltage of 1.2 and as a consequence runs slow. I have done capacity tests on these cells and at 200mA load they gave a performance of a little more than the rated 1850 mAhr. It will be interesting to see how long the cells last.

It would be nice to have measurements of the quiescent current of the regulator under no load and also under light loads to get an idea of the losses.

Thank you

excellent excellent video.. been waiting for an in depth explanation of these batteries.. if ever possible, please do a comparison.. 1.5v to 1.5v and 1.5v to 1.2v.. thanks again..

Nice review, can i know is NICD 1.2v batteries do have noise like this lithium 1.5 battery?

Thanks for the video. Can a similar analysis be done for Eneloop Lithium ION Batteries?

Goooood. I did buy 3 ....

Does the same charging mode apply to lithium battery with usb port as well?

can i use a regular nimh AA/AAA battery charger with this xstar lithium battery ?

Very well done. Over my head a bit, but I did see understand quite a bit.

I just received some AA and AAA usb type-c rechargeable both Rated for 5500mAh. I ran them down to 1.1v and measured the capacity of input energy. The AAA took 200mAh at 5V = 1000mWh and the AA took 675mAh at 5V = 3375mWh. The usealbe output capacity would be the mWh / 1.5V = 2250mAh for AA and 667mAh for AAA. I have asked how they calculate 5500mah without reply. Maybe the capacity is 5500 but only a partial amount is able to discharge. Testing 3 AAA in a small 9 LED flashlight caused damage to 2 flash lights. Flickering and burnt out LEDs while using these batteries. The switching noise was 50 to 100 mv and I suspect the flash lights received high voltage surges when the batteries were depleted. The safety circuitry is weak or non existent. Not sure if I trust using these batteries in my devices.

What would the intended use case for these be? Anything that runs from AA cells should work fine on NiMH cells unless it was very poorly designed. These have less capacity than NiMH cells while costing more than twice as much. They have a noisy output, I would imagine the self discharge rate is rather high because of the DC-DC converter, and they need a special charger.

I should be able to charge this with my XTAR VC4 charger then? Since it's just basically a 18650 type battery but in a AA size format