Quote:
Originally Posted by daniel bastida
I checked that both had a similar charge of 3.8V, and adding amperes, about 2800mAh. I connected them just to see if they would turn on the e-reader... but it didn't.
shame.
Thanks for the reply
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But they are obviously different cells and you can't parallel LiPoly directly. Also the mAH is how long the cell can supply power, not the current rating. Even a tiny 450 mAh would power an ereader.
For example, if a 1500 mAh cell gives 20 hours reading time, then a 450 mAh would give about 6 hours and 2800 mAh would give about 37 hours.
The LG pack might be really dead as it's dated 2014.
How do you know those LiPoly cells actually work?
The current rating isn't the issue. Measuring the terminal voltage with no load is also misleading. A 180 Ohm resistor is about 20 mA load, that would be a reasonable test as that might be similar to what a small screen reader takes without any front light, BT or WiFi. If a cell isn't 3.8V or more with a 180 Ohm load, it won't power (boot) an ereader.
Three flat N / Lady, AAA or AA cells is 3V, but 4.8V when fresh (though a nominal 4.5V). They would be good to test the ereader if they read 3.8V to 4.7V on your test meter with a 180 Ohm to 470 Ohm load.
Simple battery testers actually have a built in pair of load resistors for 1.5V or 9V as a digital meter can be misleading about battery/cell condition.
So your ereader might not be dead?