Winter Battery Storage

[My1999Ezgo]

So….with tons of support from this forum, I have completed my upgrade from 36v to 48v, new controller, batteries and charger. I did get about 4 years out of my old Crown 6v batteries. I want to make sure my new 8v Crowns last much longer. Living in a part of the country that has cold winters, I have always charged my batteries, removed them from the cart and stored them for about 6 months in my basement. I did not have a trickle charger on them so I think I did shorten their useful life. My questions are as follows;

1) Can I store these new batteries in my garage that is not heated, but charge them once a month with a Beleeb C20 adjustable voltage smart charger in series as a 48v pack? Will the cold damage the batteries of hinder the charging?
2) Continue to store them in the basement and use a Suuwer 8v smart battery charger and rotate charging one of them per week, rotating each battery so they get a charge once every 6 weeks?

Any suggestions on the best way to do this will be greatly appreciated! Thank you all for the support. This project has been tons of fun!!!!

[Volt_Ampere]

Batteries can tolerate cold weather if they are kept fully charged. (which you want to do for long life anyway) I don't know anything about your charger but if it keeps them charged then your option 1 is ok. If you are living there, you can keep an eye on things and check your pack voltage every so often.

[Doubles Shooter]

I use my cart all year. Cold really hasn't been an issue for charging. I start a charge cycle once a week. I drive and charge I below zero weather. The only problem is the fact batteries lose power as it gets cold. Come warm weather, all is good.

[Volt_Ampere]

Only concern with FLA batteries in winter is freezing and that is only an issue if they somehow get discharged too much. Charged FLA batteries won't freeze at normal winter temperatures.

[JohnnieB]

AT 100% SoC, the freezing point of the electrolyte in Crown brand deep cycle batteries is about -70°F (SG = 1.265) and at 70% SoC the freezing point is about -30°F. Not sure how cold it gets in your neck of the woods, but I'd try to keep the SoC closer to 100% than 70% for longevity reasons as well as freezing issues.

Get a self powered voltmeter (Powered by the voltage it is measuring.) and monitor the pack voltage. Initiate a charge cycle when the pack voltage drops down to 49.5V (80% SoC), or whatever SoC you think best.

https://www.cartsunlimited.net/battery-meters.html

Attached is a SoC chart for Crow deep cycle batteries.

[cmoon7]

Originally Posted by JohnnieB

AT 100% SoC, the freezing point of the electrolyte in Crown brand deep cycle batteries is about -70°F (SG = 1.265) and at 70% SoC the freezing point is about -30°F. Not sure how cold it gets in your neck of the woods, but I'd try to keep the SoC closer to 100% than 70% for longevity reasons as well as freezing issues.

Get a self powered voltmeter (Powered by the voltage it is measuring.) and monitor the pack voltage. Initiate a charge cycle when the pack voltage drops down to 49.5V (80% SoC), or whatever SoC you think best.

https://www.cartsunlimited.net/battery-meters.html

Attached is a SoC chart for Crow deep cycle batteries.

Thanks for the detailed info!