Now that winter is in full swing, our team has been receiving more questions about how to best winterize our batteries. Our lithium batteries are considerably easier to winterize compared to lead-acid. In this blog, we address how to take care of your batteries and system, so you can preserve your investment for more seasons to come.
With Battle Born Batteries, the winterization process is simple: fully charge the batteries to 14.4 volts and either disconnect them or engage your disconnect switch within your system to prevent a parasitic load drain during storage.
Many customers have main disconnect switches that will cut the power to the batteries, but you should take extra care that they are TRULY disconnected. Often RVs will still have a C02 sensor, backlit stereo, or some other emergency sensor that is bypassing this switch. If you are in doubt, simply disconnect the main positive and negative wires that supply your batteries. After the winter storage time, you should have plenty of charge in the batteries.
With our LiFePO4 batteries, we recommend disconnecting all potential power draws from the battery and letting them sit with a full charge, or at least a 50% charge minimum. On a full charge, our batteries have been proven to last at least a year in proper storage conditions with a 2–3% depletion each month. If left at a half charge, the batteries have the potential to not last as long in storage.
If you are storing your entire system, we recommend the use of a battery guardian to help protect your batteries by disconnecting them from parasitic loads once they reach a voltage of 11.5V. We recommend removing the main battery connections if a disconnect switch is not incorporated in your system since our batteries do not require a trickle charge.
When you return to your rig in the warmer months, they should have plenty of power and are ready to go!
Why is this important?
Our batteries have a very low self-discharge rate, measured to be 2-3% a month on average. They can also sit at any reasonable temperature and not be used with minimal concern of damage. Our batteries can handle a storage range of –15 degrees Fahrenheit to upwards of 140 degrees Fahrenheit.
If you store your batteries in subzero weather (-15 degrees Fahrenheit or less), it can potentially crack the ABS plastic and lead to a greater loss of charge. When temperatures get further towards the extremes of cold and hot, they can self-discharge a bit more than the average 3% monthly loss.
If the batteries are stored without a charge, their levels could dip below what the internal Battery Management System, or BMS, can protect over the winter season. If possible, we recommend storing them fully charged in an environment above freezing. Our team recommends not leaving a completely drained battery in that state for an extended amount of time, as it can damage the cells inside. Doing so will void the ten-year warranty that we offer with our products.
What else should I know about your batteries?
When discharging in extremely cold temperatures (less than 30 degrees Fahrenheit) there is the potential for capacity loss in the batteries. The capacity is recoverable and once the battery warms back up it will receive its full amp-hours over a period of time. At 32 degrees Fahrenheit you’ll be able to discharge 80 amp-hours, and at 0 degrees Fahrenheit you can expect a discharge 70 amp-hours. Charging a battery in extreme cold can cause lithium plating, a dangerous phenomenon that can cause short-circuiting. Our batteries have protections in place, and they will not allow a charge if an internal temperature of 24 degrees Fahrenheit is reached.
Battle Born Batteries recently explored cold temperature charging in our industry-shaking White Paper study, where we put LiFePO4 batteries to the test against AGM. Despite being in less-than-ideal temperature ranges of 26-30 degrees Fahrenheit, our batteries still delivered 175 amp-hours out of a 200 amp-hour battery bank. In this video, our COO Sean discusses how our batteries have the capabilities to outperform AGM in these cold conditions.
If you have any additional questions, our sales and tech team is always ready to help! You can give them a call at (855) 292-2831 or email them at [email protected].