Cold Lithium, too cold? (1 Viewer)

[Take2]

Hi fellow Funsters, I have a 100 amp LiFeO. Has I fitted two years ago to replace x2 wet 110‘s and they’ve been great…, until this last cold snap.
I noticed I couldn’t switch on the 12v lamp in garage and good that the vans 12v system had shut down with only 10.5v on the Lithium.
I have the van parked up for the winter all charged up but not on mains. There’s a 200W solar panel to keep it topped up which should be enough as there’s nothing switched on. Plugged mains in but Couldn’t get charged into Lithium. Same the next day so,I connected up a convector heater up which after a day got the van up to 12C but still no Lithium until the third day when the Lithium appeared 100% and didn’t drop under load. I spoke to the chap at ECOTREE who was trying to be as helpful as you can from 150 miles. I’ve had the van parked up since start of December and only used it 3 times for shopping. I always checked the power.
The Eco guy didn’t think that the cold should’ve effected things. What are your thoughts.

 

[paddymcc]

Do you know what the BMS settings are for your battery? There should be a protective cut off at above freezing to prevent charging but a lower cut off to allow discharging, probably down to -10 to -20C. Sounds as if the latter may be set too high? The battery temp may lag behind the van temp as it heats up so it could have still been below the cut off at 12C.
Some batteries seem to need a reset if they go out of their comfort zone. Check with Ecotree how to do this for next time

 

[Pausim]

LiFePO4 batteries should work well in cold weather, better than lead acid. Charging them below freezing is more problematic.

 

[Take2]

Do you know what the BMS settings are for your battery? There should be a protective cut off at above freezing to prevent charging but a lower cut off to allow discharging, probably down to -10 to -20C. Sounds as if the latter may be set too high? The battery temp may lag behind the van temp as it heats up so it could have still been below the cut off at 12C.
Some batteries seem to need a reset if they go out of their comfort zone. Check with Ecotree how to do this for next time

I did speak with Ecotree and read them the Victron BMV SETTINGS which they were happy with..

 

[Lenny HB]

I did speak with Ecotree and read them the Victron BMV SETTINGS which they were happy with..

It's the settings on the BMS you need to check thats what controls the charging /discharge limits, the BMV is just a monitor.

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[dpsuk999]

BMS not BMV. BMS is the Battery Management System built into the battery which sets all the parameters and cut offs for charging and discharging. If Ecotree supplied the battery then they will know the BMS settings as they are key to how the battery performs.

 

[andy63]

When I had a van I had one episode during the cold weather when the van was in storage with my lithium..
They appeared to have basically shutdown even though I was measuring a voltage on the terminals.
The batteries were brought back to life by bringing them into the warm and using a small old fashioned 12v charger on them for a little while..
I'm fairly sure it was because I had solar charging on them, and as has been mentioned they don't like a charge when it's very cold.. Even if they can still be used..
My thoughts from reading your issue is if you are storing the van for longish periods in winter is to make sure your lithium are reasonably well charged, isolate them and remove any charging source to them like solar.. They will be fine like that and prevent any shut down issues
Andy.

 

[andy63]

Edited... Duplicated the post.. Sorry

 

[peterc10]

Hi fellow Funsters, I have a 100 amp LiFeO. Has I fitted two years ago to replace x2 wet 110‘s and they’ve been great…, until this last cold snap.
I noticed I couldn’t switch on the 12v lamp in garage and good that the vans 12v system had shut down with only 10.5v on the Lithium.
I have the van parked up for the winter all charged up but not on mains. There’s a 200W solar panel to keep it topped up which should be enough as there’s nothing switched on. Plugged mains in but Couldn’t get charged into Lithium. Same the next day so,I connected up a convector heater up which after a day got the van up to 12C but still no Lithium until the third day when the Lithium appeared 100% and didn’t drop under load. I spoke to the chap at ECOTREE who was trying to be as helpful as you can from 150 miles. I’ve had the van parked up since start of December and only used it 3 times for shopping. I always checked the power.
The Eco guy didn’t think that the cold should’ve effected things. What are your thoughts.

As others have said LiFePo's should never be charged when they are below 0C. Did Ecotree confirm what their BMS does and if and how it deals with charging in cold temperatures? BMS's have improved over the last couple of years, and now most stop charging when approaching zero degrees.

Also what solar regulator are you using and does it have a LiFePo charging profile that it is set to and has a temperature sensor? If it does it should stop charging before the temperature reaches zero. If it doesn't you should change it to one that does, especially if your BMS does not have a built in cold charging prevention system. As you have a Victron BMV monitor best to get a Victron solar regulator and their Bluetooth temperature sensor.

The same applies with your mains charger and B2B (if you have one). To be on the safe side you need to be sure that they have a LiFePo charging profiles that stop charging when temperatures get near zero.

 

[Brian123]

i have a similar problem to Take2, my setup is....
330ah (3x110ah Ecotree lithium's)
votronic solar charger via the EBL 29
50amp votronic mains charger wired direct to the batteries
victron 30amp B2B
victron BMV712
the van has been parked up since since middle of December and was being managed at 80% charge via the setting on the voltronic main charger (This has a charging program which automatically maintains an advantageous charging state of 50-80 % of the LiFePO4 battery, when the vehicle is stopped. This charging state is advantageous for the battery lifetime and simultaneously supplies the 12 V consumer loads of body and systems, such as alarm systems, WLAN etc., as well as the vehicle's (lead) starter battery and the consumer loads in idle mode). I also removed the fuse from the votronic solar charger, so i thought that the batteries should not get a charge unless the battery SOC falls to<50% and the battery temp. was >0C.
However during the recent cold weather i noticed that the BMV was reporting the batteries were charged at 100%, I switched off the main charger and brought the SOC on the BMV down to 85%, however the BMV is also now reporting the voltage is 12.51v which according to the table below means the batteries are at 14% SOC.
I am confused and would really welcome any views as I have reached the end of my knowledge based and would like to be able have a quality conversation with Ecotree about this.

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[the1andonly]

I suspect what has happened (to OP) that the battery was discharged bellow/to minimum due to normal parasitic drains (or excessive drain due to having left something on) BMS disconnects positive termination (poor charging this winter 200W panels not up to job). The temperature drops bellow 0 (or limmit as set by BMS) so when a charger is turned on it wont accept a charge until the van is warmed up.
In previous winters the trickle charge from 200W Votronics has been sufficient to maintain the SB this year it hasn't been, requiring one top up charge. ( i use a BT Battery monitor)

 

[Bessy765]

We have Transporter Lithium they will supply current till -20c and can be charged from =4c or house lithium 2 x 5.8 kWh but dont like to take much above a trickle charge until above 5c

 

[Raul]

The recovery temperature takes time, if I have 15-18C in the van, the batteries in the cupboard can be at 8C or lower, unless I open the door. Also the bms has a low temp cut of for charging, and low temp cut of recovery. This later setting may be 2 deg higher that the low cut of. Until the temp rises above the second setting, as low temp recovery, the charging will be disabled.
Only ppl can confirm your settings are the supplier if you don’t have access to settings.
The 200w this time of year won’t do much anyways, and if it’s been cold, no charging has taken place.

 

[Take2]

When I had a van I had one episode during the cold weather when the van was in storage with my lithium..
They appeared to have basically shutdown even though I was measuring a voltage on the terminals.
The batteries were brought back to life by bringing them into the warm and using a small old fashioned 12v charger on them for a little while..
I'm fairly sure it was because I had solar charging on them, and as has been mentioned they don't like a charge when it's very cold.. Even if they can still be used..
My thoughts from reading your issue is if you are storing the van for longish periods in winter is to make sure your lithium are reasonably well charged, isolate them and remove any charging source to them like solar.. They will be fine like that and prevent any shut down issues
Andy.

Thanks for the tip. Put some heat in for a few days and battery working fine again. I noticed there was 0.3A being drawn by something. Went through removing one by one all the 12 volt fuses under the passenger seat but it was was a larger (physically) 40A fuse just off the battery that shut off the drain any ideas this fuse is for. I’ve sent an email to Pullingers

 

[VXman]

Decided to take a look at my electric motorcycle, which has been in the garage unused since November. It said it had 60% charge and did work. However it wouldn't charge. Took it inside the house for 30 mins and it's ok now. So clearly too cold to charge. Never really considered this a thing. If the battery was not removable it could be a real problem.

Do electric cars have heated batteries?

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[andy63]

Thanks for the tip. Put some heat in for a few days and battery working fine again. I noticed there was 0.3A being drawn by something. Went through removing one by one all the 12 volt fuses under the passenger seat but it was was a larger (physically) 40A fuse just off the battery that shut off the drain any ideas this fuse is for. I’ve sent an email to Pullingers

That 40amp fuse sounds like your main isolating fuse.. It would isolate the batteries totally unless you had made other connections directly to the battery posts.. Ie bypassing that fuse..
Remember that things like solar controllers and control panels will take small draws from batteries even when all else is shut down.. But. 3 of an amp is more than I would expect from say just a solar charge control..
Andy