Winter is on its way! With temperatures dropping and snow on the horizon, it’s time for solar battery owners to think about winter solar battery maintenance.
Batteries used for solar energy systems work best in warm weather. Most are rated at 77 degrees and lose about 10 percent of their efficiency for every 15- to 20-degree temperature drop from there. Shorter winter days also usually mean increased need for electricity even as less sunshine is available to generate it. This can place greater demands on your batteries, especially for an off-grid system. Proper winter battery care will help your battery bank function at the highest efficiency possible at this time, as well as prolong its useful life.

Use this handy checklist to prepare your solar battery bank for winter weather.

Store Your Batteries Properly

Batteries need to be sheltered from the weather and protected from freezing temperatures. Low-maintenance (sealed) batteries can be stored in the house. However, most solar energy systems utilize flooded batteries, which emit hydrogen gas and should be stored in a well-ventilated place away from the living area. A garage, protected shed or enclosed porch is ideal. It is best to store your batteries in a sturdy, well-vented battery box. This can be insulated, if necessary.

Perform Regular Battery Maintenance

Winter preparation is a good time to perform the periodic maintenance that most batteries need for optimal longevity and performance. You will want to check with the manufacturer for specific instructions for your battery type. However, most batteries will benefit from cleaning the terminals and making sure connections are secure. Corrosion on lead acid battery terminals can be cleaned with a mixture of baking soda and water (be sure to wear gloves) and coated with a high-temperature grease.

If you have flooded batteries, you will also need to check the water level. (This should be done every month or two; if you are not in the habit of doing this, now would be a good time to set reminders on your calendar.) If the water is low, top it off, but don’t overfill. Only use distilled water in your batteries.

Preparing Your Solar Batteries for Vacation or Extended Leave

For a vacation home that will not be used in the winter months, or if you plan to be away from home for an extended period, you’ll want to take special precautions. If you have a highly reliable generator and your inverter has an automatic generator start (AGS) function that will kick on and charge the batteries should your panels get covered in snow, you can leave the inverter on. Otherwise, turn it and all DC loads off, but leave your charge controller on.

If the system will be unattended for a very long time, you may want to disconnect your batteries for long-term storage. If you do, be sure to charge lead-acid batteries to 100 percent capacity first. If you have lithium-ion batteries, discharge them to about 40 percent. Cool temperatures (40-65 degrees) are best for long-term battery storage.

We’ll Back You Up

Don’t have time for battery maintenance, or prefer to leave it to the experts? In addition to solar battery installation, Renewable Energy Corporation offers affordable solar maintenance services to ensure optimal longevity and performance for your entire solar electric system, including your solar battery bank. Call us today or contact us here to learn more!