Keeping your LiFePO4 bank warm for charging in winter- what’s the best?

[Chotu]

I was going to move my lithium bank inside, but I really don’t think I have enough time before winter hits. There are a lot of other projects going on.

So, it will remain in its on-deck outdoor battery box.

As lithium people know, we can’t charge these batteries below freezing.

So, how are people protecting these batteries and keeping them the right temperature through the coldest of winter?

What is the best way to do that these days? I know things change a lot. I have read online about different ways to do it. There are pads. There are blankets. Maybe there’s some thing I don’t know about.

How do you keep yours warm to be able to use them through the winter?

[GordMay]

1. Insulate your battery box [Armaflex, Graphite Polystyrene (GPS) board, etc?], with removable insulation [for summer use].
2. Add a battery warmer blanket [heating pad], or other heater.
3. Reduce charging current, per manufacturers' instructions
4. Some of the newer, premium Lithium Iron Phosphate batteries*, have an integrated heater, connected to the battery's internal BMS, such that if you try and charge them, when the batteries internal temps are near, or below freezing, they divert the charging power to the heater, until they are warm enough to be safely charged.

According to RELiON: When charging lithium iron phosphate batteries below 0°C (32°F), the charge current must be reduced to 0.1C and below -10°C (14°F) it must be reduced to 0.05C. Failure to reduce the current below freezing temperatures can cause irreversible damage to your battery.

* eg: RELiON’s “LT Series” [a 12V 100Ah LiFePO4 battery] is specifically designed for cold charging, utilizing charge current to heat the battery, before allowing charge. The system features proprietary technology, which draws power from the charger itself, requiring no additional components.
With the LT series, you can charge down to -20°C [-4°F].
➥ https://www.relionbattery.com/knowle...d-temperatures

When attempting to charge a Lithium battery below 0°C / 32°F a chemical reaction referred to as “Lithium Plating” occurs. Lithium plating is caused by the charge current forcing the lithium ions to move at a faster reaction rate and accumulate on the surface of the anode.

When this chemical reaction occurs, the internal resistance of the battery increases and reduces the rate of chemical metabolism. This chemical reaction causes a permanent reduction of the battery’s capacity and will continue to reduce its capacity each time this reaction occurs.

[Chotu]

Unfortunately, I didn’t opt for the built in heaters. “I’ll never be in freezing weather.” Lol.

So the pads / blankets are still the go, it seems like.

I’m hoping they can be tied into the charge controller to allow charging after they are finished and I also hope they have temperature regulation so as not to overheat or under heat the batteries.

My battery box is R7 by default. Not amazing, but somewhat ok. Surprisingly, there is no heat when charging these things so the natural insulation factor from the foam is not an issue in summer.

[JBP]

If your cold spell is short, you can simply not charge them. You can still discharge at considerably lower temps. I believe you can program victron controllers to stop charging at low temps.
I've seen people use 12V heating pads because they didn't have shore power.

[Chotu]

Originally Posted by JBP

If your cold spell is short, you can simply not charge them. You can still discharge at considerably lower temps. I believe you can program victron controllers to stop charging at low temps.
I've seen people use 12V heating pads because they didn't have shore power.

True. I was considering maybe just T-ing off a very small bit of heat from my forced air diesel heater for heating the battery box on demand. 1” heating conduit or something, with a ball or gate valve.

More of a manual thing, but cabin heating should coincide nicely with times when I need to heat the batteries.

Or… maybe just a computer fan to blow interior air out into the battery box, which shares a wall with the galley. Even more simple.

Only issue there is I’d need to leave my heat on when I’m gone more than 3 days or shut everything down (refrigerator/freezer) depending on temps.



I wonder: if I’m at a dock for the winter as opposed to at anchor, maybe i could just remove the lithium batteries from the circuit? Drop some piece of junk 12v lead acid battery in and not have to worry about it?

[rslifkin]

Originally Posted by Chotu

True. I was considering maybe just T-ing off a very small bit of heat from my forced air diesel heater for heating the battery box on demand. 1” heating conduit or something, with a ball or gate valve.

More of a manual thing, but cabin heating should coincide nicely with times when I need to heat the batteries.

Or… maybe just a computer fan to blow interior air out into the battery box, which shares a wall with the galley. Even more simple.

Only issue there is I’d need to leave my heat on when I’m gone more than 3 days or shut everything down (refrigerator/freezer) depending on temps.



I wonder: if I’m at a dock for the winter as opposed to at anchor, maybe i could just remove the lithium batteries from the circuit? Drop some piece of junk 12v lead acid battery in and not have to worry about it?

If you're at a dock with shore power, you could definitely go for that last option if desired.



For heating from the cabin heat, you could use a fan with a temperature controller so it automatically runs when the battery box gets below a certain temperature. You could do that with heat pads as well.

[Chotu]

Originally Posted by rslifkin

For heating from the cabin heat, you could use a fan with a temperature controller so it automatically runs when the battery box gets below a certain temperature. You could do that with heat pads as well.

I like this option best. The simplicity and power savings would be very hard to beat.

A temperature controlled computer fan to blow cabin heat into the battery box (and battery box thermometer to double check) would use the least power and be able to work in all conditions. It would work at anchor, dockside or anywhere really. It could even work to help cool the batteries in the summer, although that’s never been a problem.

If you aren’t winterizing the boat, you have to maintain some semblance of heating at all times inside so the water system doesn’t freeze. So this is perfect actually.

[s/v Jedi]

The helpful answer: heating pads connected to a thermostat control. Both available on Amazon.

Obvious answers: move south of Orlando; use batteries that can be charged in freezing weather (Winston cells can do it even without heaters) when not going south during winter. Move batteries to warmer ambient (inside).

Even with the heating, you increase risk of damaging batteries greatly.

[Chotu]

Originally Posted by s/v Jedi

The helpful answer: heating pads connected to a thermostat control. Both available on Amazon.

Obvious answers: move south of Orlando; use batteries that can be charged in freezing weather (Winston cells can do it even without heaters) when not going south during winter. Move batteries to warmer ambient (inside).

Even with the heating, you increase risk of damaging batteries greatly.

I’m kind of doing the last one. I’m moving inside outside. Lol

It remains to be seen if I have a boat that sails by the time winter hits. For that reason, I have to plan for both.

I will not be motoring the intracoastal ever again. I remember that it sucked all the other times that I did it, but I really did not enjoy it this time for some reason.

It was being at a constant full alert the entire time at the helm. Yes there is keeping a watch when you are not inside of the intercoastal, but it’s an entirely different thing when you are in there. It’s like driving on the highway. A mere 30 seconds of inattention sometimes is enough to cause a problem. Hard to pee. Hard to get lunch. Constant drone of engines.

So the only way I’m going south is by wind power. At the rate these marinas are getting back to me about stepping the mast, we will see. Oddly, a vast majority of them can’t get the crane to a dock. They can only get it to the travelift well (which I can’t fit into)

Also, I think there is another reason I’m so down on the icw. It was a long journey.

I spent approximately two months going from Tampa to Beaufort, NC. Stopping every night to sleep of course. Having to stop a little bit for some issues. Provisioning. I also had some work to attend to.

But the real kicker is my sistership left on a Monday from South Florida and arrived at Beaufort, NC 2 days later on Wednesday.

I was gutted. Lol

So that’s the only way I’m traveling from now on.

Basically, looking at things quantitatively, I don’t have months to waste traveling back-and-forth. I need to work on things.

[s/v Jedi]

Maybe you have to do what Beau and Brandy did to get the mast down/up? I find that a method fully compatible with your adventures, did you see that? It’s their latest video.

[Chotu]

Originally Posted by s/v Jedi

Maybe you have to do what Beau and Brandy did to get the mast down/up? I find that a method fully compatible with your adventures, did you see that? It’s their latest video.

Or you could just tell us what the process is.

I was watching a YouTube today. It was about something with rigging. It wasted so much of my bandwith and time and they hardly touched on anything useful. A complete waste of time as usual. Just blabbering on and on and on. I don’t think you’ll ever get me to start watching tons of YouTube videos about boats. I live boats. I don’t want to watch them as entertainment. I’d rather save my bandwidth for interesting things.

That’s why I’m on here. It’s low bandwidth.

[s/v Jedi]

https://www.youtube.com/watch?v=s-LUWJ4jiXU

[Bill O]

Originally Posted by s/v Jedi

The helpful answer: heating pads connected to a thermostat control. Both available on Amazon.

Above and what Gord wrote.
Heating pads w/an inkbird digital thermostat and insulation to make a box to keep the heat in/add efficiency. Put the thermostat probe in the coldest area.

[Chotu]

Originally Posted by s/v Jedi

Oh my god. Do NOT temp me!!! Lolol.

This is exactly the type of thing I like to do. Ha ha ha.

Congratulations. With that little sales pitch picture at the beginning of the video you have convinced me to take a look. I can’t say I will be listening to all of the blabbering. But I will scrub through the video to get to the part that matters.

Way too interesting….

[Chotu]

Ok. So they used an A-frame concept to lower the mast.

That’s a lot easier than trying to build an A-frame and then raising the mast with it.

However, it’s worth a consideration. The only problem is where do you find a no wake zone that good? Ha ha.

I will think through this though. Maybe it’s OK. But you still have to get all of that wood delivered somehow and find a place to do it. You need to be at a marina for that. So I guess the crane rental is probably cheaper and more simple? Assuming I can find a crane that can reach out over a dock somewhere.

I stepped my mast on a 45ft Gulfstar using a manual crane at Castleton-on Hudson before. It was great. Right at the dock. I think this one is too tall for that crane.

Kind of would like to just go to one place and do all of this. But I have not found that place