A fully charged LifeP04 battery - Now what?

[poot_traveller]

The LiFep04 battery I received apparently came fully charged.  I read that LiFeP04 batteries can't be left in storage for more than a few days.  My LiFeP04 has been sitting around for about 2 months because I assumed it would have the appropriate amount of charge for storage. Due to storing it at 100% charged, is it possible the battery is already wrecked and requires replacement ?

Also, what is the best way to deplete the battery down to 50%?

 

[MotorVation]

What's the voltage?

No battery manufacturer would ship a battery out charged to a level that would harm them. They have no way of knowing when they're going to be put into actual use. I don't know what brand battery you have or if it has a BMS (battery management system). The BMS is designed to prevent damage that an idiot like me could cause as well as protect them from environmental factors.

I don't have my solar installed yet so I just keep a 12v fan running 24/7 and recharge the LiPo's with my charger/convertor. It helps to keep the van cooler during the day. It's still pretty hot here in Florida

 

[Lowdesertpatrol]

Its probably toast. I can maybe help you out with a few dollars for it.

 

[brahmon]

see if you had the cheapass walmart batteries like i do you could get em replaced for free

 

[poot_traveller]

What's the voltage?

No battery manufacturer would ship a battery out charged to a level that would harm them. They have no way of knowing when they're going to be put into actual use. I don't know what brand battery you have or if it has a BMS (battery management system). The BMS is designed to prevent damage that an idiot like me could cause as well as protect them from environmental factors.

I don't have my solar installed yet so I just keep a 12v fan running 24/7 and recharge the LiPo's with my charger/convertor. It helps to keep the van cooler during the day. It's still pretty hot here in Florida

12V.

It does have a BMS. But on the battery manual it says don't leave the battery fully charged when it's in storage.

It's a battery from a relatively new company.

 

[poot_traveller]

Its probably toast.

That's what I'm thinking. But I'll test it out in the weekend, I should still be able to get a bit of use out of it.

I obviously need to be present while it's charging just in case anything goes wrong. But I'll have to wait a frustrating six days before I can test it out in the weekend because I work during the weekdays.

 

[poot_traveller]

see if you had the cheapass walmart batteries like i do you could get em replaced for free

That's one advantage of having cheap Walmart batteries.

 

[MotorVation]

I should have been more specific. What actual voltage is the battery showing?  A fully charged Battleborn has a resting voltage of about 13.6 volts. When I charge mine up they're at 14.5.5 volts and then they drop down to the resting voltage. I have my charger hard wired to them so that can also affect the voltage reading. I unplug the charger from AC when they're charged and let the batteries do their thing (no float)

If you have a multi meter you put it on DC voltage then the red prong goes to the positive terminal of the battery and the black to the negative. If that battery isn't hooked up to anything it will show the real time voltage of the battery. It's difficult to tell the state of charge going by voltage alone but it should be ballpark if they're resting.

I wouldn't worry about it being fully charged if it indeed is. You can just put any kind of load on it to discharge it. If you have 12 volt appliances or lights just use them. You can do the same thing with an inverter if that's how your system is rigged. Just don't overload the system. Here's a voltage chart from Battleborn:

 

[Cajunwolf]

Dang, just hook the puppy up to a 12-volt load, a freaking 12 volt light from a car or something. Put it in your vehicle, BUT DON'T START IT, and turn on the lights and vent fan on high and discharge down to 12.2 volts, 60%, and recharge, done.
Here's a handy chart showing percentage of charge by voltage.

 

[jonyjoe303]

I leave all my lithium batteries (lifepo4/ li-ion) fully charge for months on end. Its like laptop batteries that are always plugged-in fully charge, they will still last you for years. If you keep them at half charge they will last you longer, but keeping them fully charge won't damage them.

A fully charged 4s LiFePO4 battery is 14.6 volts (3.65V per cell) , and a fully depleted LiFePO4 battery is 10 volts (2.5V per cell) but most bms won't let it get that low, they cutoff at 3 volts). When you received the battery it was probably reading 13 volts, thats the voltage a lifepo4 has when its between 10 and 90 percent. They usually ship half full from factory (13 volts). The only way to know the true charge is with a balance charger, as soon as it starts charging as each cell voltage goes up the charger will tell you what percentage it is.

Just charge it back up and will be ok, unless the bms is bad. But since it reads 12 volts (3 volt per cell) it looks like its still good, its just fully discharged. But I find it strange that just sitting around it self depleted down to 12 volts. I had a 110 ah lifepo4 stored fully charge for over an year that was still reading 13.1 volts when I brought out for use.

 

[Lowdesertpatrol]

That's what I'm thinking.  But I'll test it out in the weekend, I should still be able to get a bit of use out of it.

I obviously need to be present while it's charging just in case anything goes wrong.  But I'll have to wait a frustrating six days before I can test it out in the weekend because I work during the weekdays.

Just cut your losses now. I'll give you $100 cause Im awesome. ;D

 

[poot_traveller]

I should have been more specific. What actual voltage is the battery showing?  A fully charged Battleborn has a resting voltage of about 13.6 volts. When I charge mine up they're at 14.5.5 volts and then they drop down to the resting voltage. I have my charger hard wired to them so that can also affect the voltage reading. I unplug the charger from AC when they're charged and let the batteries do their thing (no float)

If you have a multi meter you put it on DC voltage then the red prong goes to the positive terminal of the battery and the black to the negative. If that battery isn't hooked up to anything it will show the real time voltage of the battery. It's difficult to tell the state of charge going by voltage alone but it should be ballpark if they're resting.

I wouldn't worry about it being fully charged if it indeed is. You can just put any kind of load on it to discharge it. If you have 12 volt appliances or lights just use them. You can do the same thing with an inverter if that's how your system is rigged. Just don't overload the system. Here's a voltage chart from Battleborn:

Damn it, I've just learned I could have tested it today because it's resting at 12.5V and according to the manual that means it's at 50% charge. i just didn't understand how to read the multimeter properly which made me think it was at full charge.

Anyway, Thanks for your help

 

[poot_traveller]

Dang, just hook the puppy up to a 12-volt load, a freaking 12 volt light from a car or something. Put it in your vehicle, BUT DON'T START IT, and turn on the lights and vent fan on high and discharge down to 12.2 volts, 60%, and recharge, done.
Here's a handy chart showing percentage of charge by voltage.

It turns out the battery is resting at 50% charge, I just didn't know how to read the multimeter correctly

I appreciate the help all the same.

 

[poot_traveller]

I leave all my lithium batteries (lifepo4/ li-ion) fully charge for months on end. Its like laptop batteries that are always plugged-in fully charge, they will still last you for years. If you keep them at half charge they will last you longer, but keeping them fully charge won't damage them.

A fully charged 4s LiFePO4 battery is 14.6 volts (3.65V per cell) , and a fully depleted LiFePO4 battery is 10 volts (2.5V per cell) but most bms won't let it get that low, they cutoff at 3 volts). When you received the battery it was probably reading 13 volts, thats the voltage a lifepo4 has when its between 10 and 90 percent. They usually ship half full from factory (13 volts). The only way to know the true charge is with a balance charger, as soon as it starts charging as each cell voltage goes up the charger will tell you what percentage it is.

Just charge it back up and will be ok, unless the bms is bad. But since it reads 12 volts (3 volt per cell) it looks like its still good, its just fully discharged. But I find it strange that just sitting around it self depleted down to 12 volts. I had a 110 ah lifepo4 stored fully charge for over an year that was still reading 13.1 volts when I brought out for use.

That gives me piece of mind. I ain't going to be able to do things perfectly so I like a battery that can "forgive" my dumb mistakes.

 

[poot_traveller]

Just cut your losses now. I'll give you $100 cause Im awesome. ;D

Thanks for the offer but it turns out there is nothing wrong with the battery because it was delivered to me at a resting charge of 50%. It's the owner of the battery that is the problem, I didn't know how to read a multimeter correctly.

 

[bullfrog]

Don't feel bad we all are seeing something new each day it seems and there is a learning curve.

 

[poot_traveller]

Don't feel bad we all are seeing something new each day it seems and there is a learning curve.

I cost myself more time delays because I misread a multimeter. I was supposed to be finished and living the van life by this weekend, now it's a 10 day wait

 

[BuckleBrown]

I cost myself more time delays because I misread a multimeter.  I was supposed to be finished and living the van life by this weekend, now it's a 10 day wait

Thats a bummer!
It is like being a kid and not getting to open xmas gifts until after dinner!

 

[poot_traveller]

Thats a bummer!
It is like being a kid and not getting to open xmas gifts until after dinner!

I started my van conversion 5 months ago, so I'm sure you can understand my frustration at any unexpected delays and obstacles. Every week it's the same; something unexpected holds me up another week, then another week, then another week, and on and on it goes.

I've found a way to fast track things and I'll be hopefully spending my first night in the van in 6 days now instead of 10 days.