Not all are the same, some use different doping elements, for example winston cells that used to be in victron batteries, have ythrium doping to allow discharge to -20C. That enabled mild charge under 0 deg without damage. Victron still decided to stick to 4deg threshold despite the cells would take mild charge way bellow that. I guess they wanted to protect themselves against open interpretation and accidental abuse.
Lithium batteries, solar and winter layup.
- Thread starter berni109
- Start date
I think it’s when it’s sat on the drive etc and not been used, so no heating on.
For up to a year would store them no higher than 70% charged. For 3-6 months 50-70% charged is more than enough. Anything higher will affect capacity in the long term. I only charge to 100% when I know that very shortly will be discharging and the 100% state will e for a brief short time. Only do that periodically (6times a year max) to allow top cell balance if needed. Normal cycling would see a 90-95% max charge. I allowed extra capacity for my needs to stay away of the extremities as best I can.
funflair
LIFE MEMBER
But if its sat on the drive not being used you should need not be charging the LiFePO4 batteries let them go down a bit so they are not sitting at 100% and then isolate them and only charge the starter battery if required, which is what I am going to go and set up on ours right now
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Yes I know you would face to isolate them by pulling a fuse, switch etc, it you forget it could be very expensiveBut if its sat on the drive not being used you should need not be charging the LiFePO4 batteries let them go down a bit so they are not sitting at 100% and then isolate them and only charge the starter battery if required, which is what I am going to go and set up on ours right now
As has been said Lithium will discharge to -20C, the problems come if you have a load such as I had which was a raspberry pi running Victrons Venus OS and a mifi as well as a tracker (maybe!!) allowing me to monitor the battery remotely, this was discharging at 0.5A so 12Ah a day.
Lithium should not be taken flat, the BMS will cut off but if the load is still there it will continue to drain, very very slowly, the BMS has a standing current too. This means you may not get the Lithium back into service if it goes too flat.
My solar setup 160W couldnt provide 12Ah of charge leading up to Christmas and then since the New year in Northamptonshire the temp has only risen above 5C on a couple of days so my Lithium would be completely stuffed particularly as the moho is well insulated so would take a sizeable amount of time to warm up.
And we are in lockdown and its in storage which isnt open so I substituted a Lead Acid while its over wintering in Lockdown, I also turned off the monitoring. In my mind its too expensive a battery to leave condition unknown during a pandemic. I think though had I left it with no monitoring system even now it would be around 50% but I wasnt prepared to take the risk as the weather is just not warm enough.
I left the 150Ah at 50% state of charge when I disconnected. I put the Lead Acid in there to allow the solar to carry on maining a battery but more importantly trickle charging the vehicle battery, that wouldnt happen if the leisure battery was disconnected in my system.
If I was living in it it would be fine because the battery would be at 18-20C and would charge at he slightist hint of sun.
I would not go back to lead acid as the advantages of Lithium far outweigh this minor inconvenience made even worse by Lockdown
Lithium should not be taken flat, the BMS will cut off but if the load is still there it will continue to drain, very very slowly, the BMS has a standing current too. This means you may not get the Lithium back into service if it goes too flat.
My solar setup 160W couldnt provide 12Ah of charge leading up to Christmas and then since the New year in Northamptonshire the temp has only risen above 5C on a couple of days so my Lithium would be completely stuffed particularly as the moho is well insulated so would take a sizeable amount of time to warm up.
And we are in lockdown and its in storage which isnt open so I substituted a Lead Acid while its over wintering in Lockdown, I also turned off the monitoring. In my mind its too expensive a battery to leave condition unknown during a pandemic. I think though had I left it with no monitoring system even now it would be around 50% but I wasnt prepared to take the risk as the weather is just not warm enough.
I left the 150Ah at 50% state of charge when I disconnected. I put the Lead Acid in there to allow the solar to carry on maining a battery but more importantly trickle charging the vehicle battery, that wouldnt happen if the leisure battery was disconnected in my system.
If I was living in it it would be fine because the battery would be at 18-20C and would charge at he slightist hint of sun.
I would not go back to lead acid as the advantages of Lithium far outweigh this minor inconvenience made even worse by Lockdown
Good thinking but the vast majority of people wouldn’t do that, they need to be fit and forget at all times for most.
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Yes I agree but you will always be stuck with not being charged below 0C for all Lithium including your phone! so most will have to wait for a new chemistry.
Relying on heat mats etc will not help over winter as its the battery providing the power for the heat, Tesla cars are the same, in fact all EVs are like that.
Lenny HB
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I would class that as a heated locker, when people refer to their batteries are in a heated locker they are comparing it to some vans where the batteries are in an external locker.
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As this thread is about laying-up for winter (or an even longer period under current circumstances) I'm surprised that the state of charge has not been discussed.
I understand that Lithium should be somewhere between 50% and 75% charged (not fully) if left for long periods.
How are people achieving that?
Once within that band, I'd suggest disconnecting/isolating them as they should not discharge after that and will need no further attention.
I understand that Lithium should be somewhere between 50% and 75% charged (not fully) if left for long periods.
How are people achieving that?
Once within that band, I'd suggest disconnecting/isolating them as they should not discharge after that and will need no further attention.
Nasher
Free Member
When I'm parked up in Austria and it's -20 degrees plus the wind chill factor, there is no way it is a heated locker - quite often there is ice on the inside of the van and the doors won't open because they're iced up!
I'm pretty sure that Lithium is the way to go in the future, but reading on this thread about Bluetooth temperature sensors, heat pads, Bluetooth networks, disconnecting the battery when cold, a thermometer taped on the battery case, etc. it's not for me
My motorhome is a tool designed to carry me & my toys to a destination and, where necessary, provide somewhere to cook, eat & sleep
The last thing I want to do is check inside & outside temperature, the weather forecast, deciding whether to disconnect the battery or whether the battery is 50% charged if I'm not going to be using it for a while, etc
Now, I know many on here like their gadgets and tinkering, nothing wrong with that, but for me life's too short to spend that much time for 12 volts
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Yes that’s my thinking, plus these fit and forget x2 140amp Deta gels are original batteries, now on their 16th year, soon 17th year of age. Van on the drive is often encased in ice up here on the moors.When I'm parked up in Austria and it's -20 degrees plus the wind chill factor, there is no way it is a heated locker - quite often there is ice on the inside of the van and the doors won't open because they're iced up!
I'm pretty sure that Lithium is the way to go in the future, but reading on this thread about Bluetooth temperature sensors, heat pads, Bluetooth networks, disconnecting the battery when cold, a thermometer taped on the battery case, etc. it's not for me
My motorhome is a tool designed to carry me & my toys to a destination and, where necessary, provide somewhere to cook, eat & sleep
The last thing I want to do is check inside & outside temperature, the weather forecast, deciding whether to disconnect the battery or whether the battery is 50% charged if I'm not going to be using it for a while, etc
Now, I know many on here like their gadgets and tinkering, nothing wrong with that, but for me life's too short to spend that much time for 12 volts
Thanks for all the replys and useful information.
I will attempt to summarise the answers and I am sure if I get it wrong someone will tell me.
But firstly let me say that the statement that a lithium battery(lb) is a drop in replacements is complete bullshite!
Lb can be stored at 50 - 70% of full charge disconnected from the hab electrics for 3 - 6 months without deterioration. (Seems to be the consensus).
Lb should NOT be charged near to or below 0°C. Some lb may have a BMS that will stop this charge taking place but you need to carefully check that or you will distroy the lb. in short order.
If you are going to leave your lb connected to the solar controller(sc) you should ensure that it has a lb charge profile and the battery has a temperature sensor connected to the sc. So as not to attempt to put amps into the lb. at very low temperatures.
If you leave your lb connected to solar and temperature is above 0C° it could be taken up to the maximum state of charge 100% if there is no drain on the lb from hab demand which is not a good situation to leave a lb in over extended periods.
You can safely use the agm setting on an elecktroblock charging system on hookup or with the alternator running but only if the lb temperature is above 0°C
You need a B2B device to protect the alternator with a lb and some means of stopping it pushing amps to the lb if its temperature is 0°C
So for safty during an extended layup I will disconnect the lb.
I will attempt to summarise the answers and I am sure if I get it wrong someone will tell me.
But firstly let me say that the statement that a lithium battery(lb) is a drop in replacements is complete bullshite!
Lb can be stored at 50 - 70% of full charge disconnected from the hab electrics for 3 - 6 months without deterioration. (Seems to be the consensus).
Lb should NOT be charged near to or below 0°C. Some lb may have a BMS that will stop this charge taking place but you need to carefully check that or you will distroy the lb. in short order.
If you are going to leave your lb connected to the solar controller(sc) you should ensure that it has a lb charge profile and the battery has a temperature sensor connected to the sc. So as not to attempt to put amps into the lb. at very low temperatures.
If you leave your lb connected to solar and temperature is above 0C° it could be taken up to the maximum state of charge 100% if there is no drain on the lb from hab demand which is not a good situation to leave a lb in over extended periods.
You can safely use the agm setting on an elecktroblock charging system on hookup or with the alternator running but only if the lb temperature is above 0°C
You need a B2B device to protect the alternator with a lb and some means of stopping it pushing amps to the lb if its temperature is 0°C
So for safty during an extended layup I will disconnect the lb.
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Lenny HB
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Most people in those temperatures would leave the heating on 24/7.
Nasher
Free Member
With the charging issues of lithium batteries at low temps how do the likes of Tesla and in the future electric MHs overcome charging in winter?
I am giving up on Lithium right now. I want to be able to leave and forget, which isn't possible. In my MoHo this morning it is a chilly 0 degrees. I don't want a system that needs pampering.
Lithium battery for sale in the classified..... Along with all the Victron gear I bought.
Lithium battery for sale in the classified..... Along with all the Victron gear I bought.
They shouldn’t need pampering, the battery management system does that. They also don’t lose performance in cold weather, unlike lead acid.
Lead acid battery charging in cold weather - Victron Energy
This blog covers lead acid battery charging at low temperatures. A later blog will deal with lithium batteries. Charging lead acid batteries in cold (and indeed hot) weather needs special consideration, primarily due to the fact a higher charge voltage is required at low temperatures and a lower...
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Agree that the BMS should take care of everything but not all BMSs are equal and you have little idea how good each one is.They shouldn’t need pampering, the battery management system does that. They also don’t lose performance in cold weather, unlike lead acid.
Lead acid battery charging in cold weather - Victron Energy
This blog covers lead acid battery charging at low temperatures. A later blog will deal with lithium batteries. Charging lead acid batteries in cold (and indeed hot) weather needs special consideration, primarily due to the fact a higher charge voltage is required at low temperatures and a lower...www.victronenergy.com
A point with Lithium vs Lead is that replacement of Lead is a lot more affordable.
Assuming BMS allows charging upto 100% state of charge (why wouldn't it) then during layup over several months with loads of solar on the roof the lithium battery will constantly be 100% without anything consuming that power. Not good for longevity of lithium batteries.
Unless u have an all sining all dancing solar controller that stops charging at a set % SOC.
Unless u have an all sining all dancing solar controller that stops charging at a set % SOC.
If there is no load on the battery during lay up all you need to do is disconnect it when less than 100% full, they lose only an insignificant amount of charge thereafter. If there is a small load which you need to cater for just set the charge voltage for a bit less than needed for a 100% charge. Relion say charge to 14.4V for winter storage which is the normal voltage output for a gel battery. Laying up LiFePO4 batteries is no more difficult than lead acid and for many the low self discharge is a real benefit.
other points from my similar thread recommended by funsters.
It's safe to leave solar panels disconnected from the solar controller during layup. Removes any solar charge from the battery.
Dont leave panels connected to controller and disconnect the battery. Potential damage to the controller.
It's safe to leave solar panels disconnected from the solar controller during layup. Removes any solar charge from the battery.
Dont leave panels connected to controller and disconnect the battery. Potential damage to the controller.
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Thanks for your info, really informative, but having problem , never did get to grips with motor vehicle electrics, after 50 years + in motortrade, basics I'm okay , thanks again, I never cease to be impressed about what knowledge we can gai from this great website
I had the misconception you were a "hardened" welshman. O no must be an immigrant.I stay in a (minimum) four star hotel - normally for 4 weeks
Ps i emegrated many moons ago.
Nasher
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£15 off Amazon pre Covid
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