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Topic: [Solved]Measure a battery amps (Read 8333 times) previous topic - next topic

jbarchuk


humm then i already have similar to that =)
I would go with a charger that doesn't need changes :P


You are free to add a tiny board that adds a DIP switch that patches in different resistors.

You are free to add an digitally controlled potentiometer that switches the resistors under keypad/LCD control.

You are free to plug all that into an Arduino with a library of battery specs, that you pick the battery and it knows how to set the digital pot.

Orrrrr you can go buy a charger that already has those features in it. Well, not the library of specific batteries, but you tell it the mA and it does the rest.

Arduino is all about the 'exercise for the student.' If you want to be the student and design/build it, then do it. If you just want the device to use it, then it's already available.

Zapro


Correct and you most likely destroyed the battery cell. Li-po cells should never be allowed to discharge below 3.0 volts.



Matbe you overlooked the fact that OP is using a Nokia-pack, and therefore (if it's not one of those clones that's extremely dangerous) it's a protected pack. These kind of batteries are almost idiot- and fool-proof. Over-discharge them, and they'll go open circuit until you try to charge them again. Short-circuit them, and they'll go open circuit. Over-charge them and they will go boom though :D

// Per.

tsunamy_boy

Ok no, it was a cheap lipo ebay battery, but once i add current back again it got back to life instantly.
But yes, it might have become a clock bomb :O

polymorph

What exactly do you want to know?

How many Amp-hours are in the battery? We can help you with that.

What is the maximum current you can safely draw from that battery? For that, you need to ask the seller or find the manufacturer of the battery and ask them.
Steve Greenfield AE7HD
Drawing Schematics: tinyurl.com/23mo9pf - tinyurl.com/o97ysyx - https://tinyurl.com/Technote8
Multitasking: forum.arduino.cc/index.php?topic=223286.0
gammon.com.au/blink - gammon.com.au/serial - gammon.com.au/interrupts

tsunamy_boy


How many Amp-hours are in the battery? We can help you with that.


Well if you could explain it with more detail i would be grateful yes :)

polymorph

Ah or Ahr is Amps times hours. So if a battery is 1Ah, you can draw 1A from it for one hour if starting from a full charge.

However, batteries are normally rated by drawing enough current to last 10 hours, then multiplying that by 10. The faster you draw current from a battery, the less efficient it is, so a 1Ah battery may only give you 1A for 45 minutes before it is empty, but go 10 hours on 100mA.

So you need to start with an approximate number. How large is the battery? What kind of battery?
Steve Greenfield AE7HD
Drawing Schematics: tinyurl.com/23mo9pf - tinyurl.com/o97ysyx - https://tinyurl.com/Technote8
Multitasking: forum.arduino.cc/index.php?topic=223286.0
gammon.com.au/blink - gammon.com.au/serial - gammon.com.au/interrupts

tsunamy_boy


Ah or Ahr is Amps times hours. So if a battery is 1Ah, you can draw 1A from it for one hour if starting from a full charge.

However, batteries are normally rated by drawing enough current to last 10 hours, then multiplying that by 10. The faster you draw current from a battery, the less efficient it is, so a 1Ah battery may only give you 1A for 45 minutes before it is empty, but go 10 hours on 100mA.

So you need to start with an approximate number. How large is the battery? What kind of battery?


Well i have a lot of kinds of batteries, but i got your idea and it was great because i learned something more. I didn't know that thing about 10 hours 100mA.
Thanks mate :)

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