Li-ion battery drain to 0.4V

Anyone got any ideas why my 3000maH Li-ion battery drains after about one day of use on LCD and arduino project?

Drops to incredibly low voltage of 0.4V, and then if i charge it, restores voltage to 4V in a couple minutes.

Circuit “diagram” attached. I’ve got two boost converters to power arduino and solenoid, and charger in parallel as well

I did solder the battery contacts, although have tried another battery without and seems to have same problem.

It's dead. You need a new one.

I have tried a new one and same problem - same battery make (cheap from aliexpress may be problem)

Bin it, do not attempt to recharge a lithium battery that has gone that low, especially if you live anywhere near me.

(South Wales, UK)

Not sure why your asking the forum as to why it drains so fast, you have the battery and circuit so measure how much current your project is drawing ..................................

Anyone got any ideas

Your circuit draws a lot of current, and destroys the battery within one day. Never allow the voltage to drop below about 3.0V.

It's possible that the 0.4V is a result of battery protection kicking in, and it isn't really discharged that low. And if it recharges to 4V rapidly, it may be that over-current protection kicked in. Just a guess, but if this happens with two different batteries, some explanation like this becomes more probable. Of course I'm assuming you're using protected batteries. If you aren't, then they really are discharged that low, and are no longer to be trusted.

If my understanding is correct, your boost converters will draw increasing current from the battery as the battery voltage drops. That might explain why you only get this after a day if it is only then that the excess current limit is reached in the protection circuit.

Also, what do you plug into the charger to recharge the battery? And do you disconnect the load while you are charging?

If my understanding is correct, your boost converters will draw increasing current from the battery as the battery voltage drops.

Correct.

ShermanP:
It's possible that the 0.4V is a result of battery protection kicking in, and it isn't really discharged that low. And if it recharges to 4V rapidly, it may be that over-current protection kicked in. Just a guess, but if this happens with two different batteries, some explanation like this becomes more probable. Of course I'm assuming you're using protected batteries. If you aren't, then they really are discharged that low, and are no longer to be trusted.

If my understanding is correct, your boost converters will draw increasing current from the battery as the battery voltage drops. That might explain why you only get this after a day if it is only then that the excess current limit is reached in the protection circuit.

Also, what do you plug into the charger to recharge the battery? And do you disconnect the load while you are charging?

Thank you for your reply and very good suggestion. No I do not disconnect the load while charging. Is this a problem? I will monitor how much current is passing through the battery and get back to you

I do not disconnect the load while charging. Is this a problem?

Yes.

Tell us more about the battery: post a link to where you bought it. It may have a battery protection circuit built in.

Tell us more about how you are charging the battery.

The commonly available Li charger modules, like the TP4056, do not work properly if the battery is connected to the load while charging.

willpowell:
I have tried a new one and same problem - same battery make (cheap from aliexpress may be problem)

You must have had bad luck. I have bought over 150 18650 batteries from aliexpress (and 180+ NiMh) batteries. All of the 18650 batteries have been good. Only two of the NiMh batteries was dead.

The battery is not the problem.

jremington:
Tell us more about the battery: post a link to where you bought it. It may have a battery protection circuit built in.

Tell us more about how you are charging the battery.

The commonly available Li charger modules, like the TP4056, do not work properly if the battery is connected to the load while charging.

Here is the link to the batteries:

I have tried using what i think is a genuine panosonic one - the current draw at start was 60mA at 3.7V and now 110mA since battery declined to 1.7V.

Still not high current but boost converter only boosting 2.1V to arduino (although still manages to boost 11.8V to solenoid). I have not tried charging yet, although i have mad a PCB so that it will be charging (TP4056 charger) with a load.

Any suggestions appreciated!

I have tried using what i think is a genuine panosonic one - the current draw at start was 60mA at 3.7V and now 110mA since battery declined to 1.7V.

The battery has been destroyed by allowing the voltage to drop well below 3.0V. Please dispose of it properly and safely.

The batteries you linked do not have over-discharge protection.

I think you need to grab new one!

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