Self Heating, Renogy 12v Smart 100ah Lithium Batteries

[JamesAdam]

https://www.renogy.com/12v-100ah-sm...te-battery-w-self-heating-function-pre-order/

This is the best solution for a van Deep Cycle Battery (in my opinion) is a self - heating lithium battery that works in cold weather!  Easy to connect them together with Cat-5 Cable so they equalize automatically.

I copied the description from their website.

[font=Biryani, sans-serif]DESCRIPTION[/font]

[font=Biryani, sans-serif]【Uncompromising Quality】 [size=small]State-of-the-art battery cells ensure a lifespan of more than 4000 cycles, 100A continuous discharge current, and a wide range of operation temperature.
【Self-Heating Function】 The intelligent self-heating function will start operating automatically once the battery’s core temperature drops below 41°F (5°C), effortlessly keeping your battery charged in cold environments.
【Reliable BMS System】 The state-of-the-art battery management system (BMS) with high-performance dual-processors provides short circuit, over charging and over-temperature protection while maintaining a balanced voltage across all cells.
【Auto-balancing Function】 Easily connect multiple batteries in parallel with the auto-balancing function to improve the average charging efficiency for your batteries in the long term.
【Real-time monitor】 The battery features RS485 communication ports—enabling communication between batteries, external devices (BT-2 Bluetooth Module or Monitoring Screen) and host computers for you to monitor the charging status in real-time in Renogy DC Home APP.[/font][/size]

 

[Sofisintown]

The self-heating battery will drain itself faster then you like trying to keep itself warm.
Try to keep the inside of your vehicle (and yourself and the battery) above freezing temperatures with a small propane heater that uses no electricity.
And for Pete's sake, stay away from places that are freezing cold. You got wheels. Head south!

 

[gizmotron]

Hahahah! LOL that is my plan. I have a van design that has a natural cold spot where I store the batteries. But I figured out that I would not be taking a shower when the van's living space is below freezing. So I'm putting in a water proof pair of doors in the shower wall that have low wattage 12v DC box fans built behind them that circulate the warm air from the living space in and out of the colder mechanical room. That room is insolated and will hold on to any heat coming from the living space. I might even put a thermostat on those fan motors. 

Once you start to think about how they would do it on the International Space Station then you can do it in your own solar powered space station.

 

[DLTooley]

The thermal mass of a battery is such that a brief dip below freezing won’t be a problem. A temperature controlled BMS like the overkill will protect you in the rare exceptions.

Living space, as above, is even better.

 

[tx2sturgis]

The self-heating feature is really designed to keep the batteries at or above freezing while they are being charged in a cold environment.

Obviously if they were left in subfreezing temps, not charging, and with the heater activated, they would eventually self-discharge. 

But there is really no reason to keep the heater running if you are not actively charging the batteries, and I believe that 'smart' battery will not activate the heater function unless there is a charging input.

And they can tolerate normal sub-freezing temps if they are not in use.

 

[ldsreliance]

My Jericho batteries have this function, too. I can't speak to the Renogy batteries but the heater in my batteries does not operate until a charger is connected AND it is colder than freezing. To be clear, the internal heating element does not and cannot pull power from the battery itself. It can only pull power from a charger that is connected to the terminals and the BMS tells it that it is cold enough to engage.

I tested this on my batteries recently to see how it works by putting one in a chest freezer for 2 days. Pretty interesting video if you have a few minutes:

 

[tx2sturgis]

Thanks for that test, and your testing methods seem spot-on. 

I have seen other brand 100A LiFePo4 drop-ins that actually have a wire you attach to the positive terminal to engage the heater, and that design will probably drain the battery to the cut-off voltage if left in subfreezing temps, not hooked to a charger, and with the heater wire attached to the terminal.

Most owners would, we assume, have enough common sense to not allow their $1000 heated battery to deplete itself un-attended, but sometimes things happen.

 

[gizmotron]

Most owners would, we assume, have enough common sense to not allow their $1000 heated battery to deplete itself un-attended, but sometimes things happen.

Wow. I wonder if this is why my new Lifepo4 200ah battery does not have an automatic cold temp shutdown during charging in the BMS. It forces the owner to use diligence in cold temps. Some advance chargers have a shut down feature built into them for cold temps. We are clearly in the infancy stage for Lifepo4 battery tech. The prices keep falling to the point that it's cheaper to go with one of them than to get several AGM's.

 

[ldsreliance]

Thanks for that test, and your testing methods seem spot-on. 

I have seen other brand 100A LiFePo4 drop-ins that actually have a wire you attach to the positive terminal to engage the heater, and that design will probably drain the battery to the cut-off voltage if left in subfreezing temps, not hooked to a charger, and with the heater wire attached to the terminal.

Most owners would, we assume, have enough common sense to not allow their $1000 heated battery to deplete itself un-attended, but sometimes things happen.

Yes, that is how a lot of them work, including from BattleBorn.  But that requires the end user to have some diligence, as has been said, and requires that you can gain physical access to the battery, too.  Some people have their batteries in a tight spot or are just lazy and want everything automated and so this Renogy and my Jericho batteries are the next evolution of the self-heated batteries.

Hopefully Renogy was smart enough to not allow the heater to deplete the battery itself but I can't say for sure.

 

[JamesAdam]

Hello,
Thanks for the replies.

I copied this from the Renogy Users Manual.  https://www.renogy.com/12v-100ah-smart-lithium-iron-phosphate-battery-w-self-heating-function/

Self-heating Function
The normal operation of the self-heating function requires a stable charge current greater than 4A
for each battery in the parallel battery bank. The self-heating function will start operating automati-
cally once the battery and the battery temperature drops below 41°F (5°C) and stop operating
automatically once the battery temperature rises above 50°F (10°C).
The self-heating function will not be able to operate normally if a PWM charge controller or
a small current battery charger is used to charge the battery at low temperatures.


I won't use propane in my van.  I'm all Electric, including my Ceramic Heater, so I want to be able to charge my Batteries in Freezing Weather.

 

[tx2sturgis]

I won't use propane in my van.  I'm all Electric, including my Ceramic Heater, so I want to be able to charge my Batteries in Freezing Weather.

This is not going to work out for you with solar power long term OR short term on freezing cold days and nights in sustained cloudy/inclement/snowy weather.

Unless you have consistent access to shore power, and it sounds like you don't or won't.

You will be needing a backup when your planned heating system fails.

 

[jimindenver]

this Renogy and my Jericho batteries are the next evolution of the self-heated batteries.

LifeBlue has offered this option for at least three years and they were the second company to offer it.

 

[JamesAdam]

I have two Mr.Buddy Golf Cart Propane Heaters.  I have had warranty replace them several times because they just stop working.  Unreliable, I don't trust them.  Beside, Propane Heat is mostly water vapor.  In the frosty mornings I  would have to scrape the inside of my windows with a Ice Scraper.   I won't use them.

I have 400 Watts Solar, 40 Amp Mppt charge controller, a DC/DC Charger and two Renogy 100ah Self Heating Lithium Batteries.  My Ceramic Heater with a Thermostat works from 400 Watts to 1,500 Watts.  In the winter, I leave it running 24 Hours a day.  

I don't live in my van.  I just want it warm when I use it in the winter and also be able to use it as a campervan.  

Hello,
Thanks for the replies.

I copied this from the Renogy Users Manual.  https://www.renogy.com/12v-100ah-smart-lithium-iron-phosphate-battery-w-self-heating-function/

Self-heating Function
The normal operation of the self-heating function requires a stable charge current greater than 4A
for each battery in the parallel battery bank. The self-heating function will start operating automati-
cally once the battery and the battery temperature drops below 41°F (5°C) and stop operating
automatically once the battery temperature rises above 50°F (10°C).
The self-heating function will not be able to operate normally if a PWM charge controller or
a small current battery charger is used to charge the battery at low temperatures.


I won't use propane in my van.  I'm all Electric, including my Ceramic Heater, so I want to be able to charge my Batteries in Freezing Weather.

This is not going to work out for you with solar power long term OR short term on freezing cold days and nights in sustained cloudy/inclement/snowy weather.

Unless you have consistent access to shore power, and it sounds like you don't or won't.

You will be needing a backup when your planned heating system fails.

 

[ldsreliance]

LifeBlue has offered this option for at least three years and they were the second company to offer it.

Yep.  And they are made by the same manufacturer that I use.  But theirs has evolved over time, as well.  It was not the same 3 years ago.  Getting the heating film to work the way it does now is actually a pretty neat bit of engineering.