Amp hour batteries

[Gstan]

I bought some of these for my bowfishing rig. $500 from Amazon. They easily last twice of my group 31 Duracell AGM batteries.
However after I bought them I found out the BMS does not have a low temp cut off.
The last thing I want to do is wreck my batteries.
I use my boat until end of December so I'm constantly charging them in the garage. Nothing has ever frozen in my garage, water etc. So that means nothing goes below 32°.
Should I be worried about charging them? It would be a hassle of bringing them in everyday and leave them overnight and charge them in the morning.
Your thoughts?

 

[KD5UND]

Be sure when charging to take the temp of the batteries, not just the surounding ambient air. It's the temp of the battery itself that matters

 

[chrisski]

Victron makes a battery sensor you attach to the battery that will hook to their controller that will shut off the SCC from charging that way.

If the battery is charged by any other method like shore power or an alternator, that won’t shut it off. So, the battery in your garage overnight or driving down the road and when the boat is put in the water, some charging comes on from the boat when the battery is below temp, that’s what I’d worry about. With the battery temp sensor I mentioned, that will tell you temps are too low, will shit off Victron devices from charging, but won’t stop anything else. All you could do in that case is check the battery and wait for it to warm up.

Only other thing is a heating pad.

Without reading the battery specs, I don’t know what to tell you about the cutoff temp.

 

[Gstan]

Be sure when charging to take the temp of the batteries, not just the surounding ambient air. It's the temp of the battery itself that matters

And how do I take the temperature of the battery?

 

[Gstan]

Victron makes a battery sensor you attach to the battery that will hook to their controller that will shut off the SCC from charging that way.

If the battery is charged by any other method like shore power or an alternator, that won’t shut it off. So, the battery in your garage overnight or driving down the road and when the boat is put in the water, some charging comes on from the boat when the battery is below temp, that’s what I’d worry about. With the battery temp sensor I mentioned, that will tell you temps are too low, will shit off Victron devices from charging, but won’t stop anything else. All you could do in that case is check the battery and wait for it to warm up.

Only other thing is a heating pad.

Without reading the battery specs, I don’t know what to tell you about the cutoff temp.

Do you have a link to that?
These batteries are for my trolling motor and my lights. They are not being charged but by anything on the boat. I have a separate starting battery that is not lithium.
I charge them when I get home with a 20 amp charger. Would that work with that? You mentioned a controller and I'm not sure what you mean about that either

 

[chrisski]

The temp sense will be in the products link here:

victronenergy.com

 

[rmaddy]

I believe this is it:

Smart Battery Sense - Victron Energy

Improve the charging-efficiency and prolong the life of your batteries with the Smart Battery Sense. Find a dealer near you.

www.victronenergy.com

 

[chrisski]

I believe this is it:

That is it. Please note this device is Bluetooth connection and will work with Victron Devices only.

I am building a Large Lithium Battery and have one of these SMART BATTERY SENSE left over. I have a BMS with two temp sensors. The BMS will do a low temp shutdown, but I will still use this SMART BATTERY SENSE as the primary means. The Smart Battery Sense will shut off the Victron SCCs at perhaps 35 F, and then at a 32 F the BMS will shut off charging.

The SMART BATTERY SENSE for me would do all the work shutting off the charge controllers, and the BMS would be there in case someone turned on the generator to charge up the battery bank when its below freezing.

 

[Gstan]

I believe this is it:

Smart Battery Sense - Victron Energy

Improve the charging-efficiency and prolong the life of your batteries with the Smart Battery Sense. Find a dealer near you.

www.victronenergy.com

It looks like that only works with their solar chargers.
I have 20 amp lithium chargers. They are not blue tooth.

 

[chrisski]

It looks like that only works with their solar chargers.
I have 20 amp lithium chargers. They are not blue tooth.

I know of no easy solution for turning on and off the Battery charger based off temperature. A general idea is to use a contractor relay tied to a temp switch, but engineering that is a bit more complicated.

 

[Gstan]

I know of no easy solution for turning on and off the Battery charger based off temperature. A general idea is to use a contractor relay tied to a temp switch, but engineering that is a bit more complicated.

What temperature will I get in trouble with? I could buy an infrared temperature reader just make sure the batteries are above that?

 

[chrisski]

That will be on th e battery spec sheet. Can be 32 F or a little colder for the ones I know.