Maintaining Solar Deep-Cycle Batteries During Self Quarantine and Stay-At-Home Orders

With stay-at-home orders in place in many states, homes utilizing deep-cycle batteries for power could be increasingly straining their systems. As more people stay home, more appliances and electrical accessories that would typically be off during the day will be used. Add to that the fact that storms could reduce the amount of energy being generated by solar panels.

To avoid putting additional strain on your battery storage system, there are several ways you can keep deep-cycle batteries in good working order.

1) Minimize your battery-packs depth-of-discharge (DOD) to no more than 50 percent. Draining past 50 percent DOD will ultimately shorten the lifespan of your battery pack. If possible, schedule times during the day when certain non-essential items can be turned off. This will help minimize the total discharge.

2) If your home is plugged into the electrical grid. Use this opportunity to charge your deep-cycle battery pack to keep them from discharging below 50 percent.

3) Perform an equalization charge. Equalization charging prevents the build-up of sulfates on the battery plates that can reduce capacity. The batteries should be fully charged before any equalization charge is added.

4) Check water levels on flooded lead-acid deep-cycle batteries. Make sure the batteries are fully charged first, then add water as necessary to fill each cell, ensuring the plates are fully submerged.

5) Keep your battery area clean and check for corrosion and proper battery connections. Check the cables to ensure they are tight. Remove any corrosion with a mixture of water and baking soda.

6) Double-check charging rates during cold temperatures. Flooded lead-acid batteries charge and discharge differently in cold and hot temperatures. During winter months, it may take longer for batteries to recharge. The best way to ensure the batteries are fully charged and not dipping below 50-percent DOD is to use a hydrometer to measure the specific gravity of each battery cell.

Battery manufacturers recommend using a simple correction factor to your hydrometer’s readings. Using 80-degrees as your baseline, subtract (.004) from your hydrometer reading for every 10-degrees below 80 °F (5.6-degrees below 27 °C). For example, if the temperature of the electrolyte is 50 °F and your battery specific gravity reading is 1.200, you must subtract .012 from your measurement. In this case, .004 for every 10-degrees equals .012. Subtract this from 1.200, and your corrected specific gravity reading is 1.188.

Paying closer attention to your renewable energy system’s deep-cycle batteries will ensure they will remain reliable and get you through what could be several weeks or months of having to stay indoors during this outbreak.


Experienced Off-Grid Homesteaders Believe Flooded Lead Acid Batteries Are Still The Best Choice For Renewable Energy Systems

Batteries used for energy storage are necessary for any off-grid homestead or cabin. For experienced off-grid homesteaders, managing power storage from renewable energy sources is something they become good at, and over the years, the choice of batteries for experienced homesteaders like Allan Sindelar, a licensed electrician, and homesteader who has been living off-grid for more than 25 years, he still prefers deep-cycle flooded lead-acid batteries (FLA) for the job. “Few off-grid installers have been selecting, installing, and maintaining batteries long enough to learn from entire battery life cycles,” said Sindelar in his article The Best Batteries For Your Off-Grid Battery Bank that was published in Mother Earth News. “Without much long-term data, we tend to use what has worked previously, rather than trying new and possibly expensive approaches.”

Sindelar recalls when early homesteaders were using two car batteries 30 years ago, but once the FLA batteries became more affordable, off-grid homesteaders settled on using the L16 FLA batteries for their performance and reliability. “These are well-sized for small-to-medium systems and are available at a relatively low cost.” Sindelar also says in his article that experienced homesteaders are often better at performing routine maintenance which can lead to FLA batteries lasting greater than six years or more.

With other battery types trickling into the off-grid industry, Sindelar believes the data isn’t there to determine if they are a better solution over the long-run. “While tremendous advances are taking place in battery development, most are based around increasing a battery’s performance and energy density per pound, that is, lightweight, high-capacity batteries for electric vehicles and portable applications,” says Sindelar. “In homestead systems, weight isn’t a key factor. For most homesteaders, conventional flooded lead-acid batteries still fit this bill best.”

The appeal of batteries with no maintenance is big among new homesteaders, but Sindelar believes there are drawbacks. “Sealed batteries are substantially more expensive and more susceptible to damage from overcharging,” says Sindelar. “They’re well-suited to homeowners who don’t want to perform their own battery maintenance, as the charge for professional service several times each year adds up. This group might include many newcomers to off-grid living, who value the benefits but don’t desire the DIY involvement of earlier generations.”

As battery technology increases Sindelar believes it’s a good idea to use tried-and-true flooded lead-acid batteries until the various choices of batter types become clear in this form of use. “Homesteaders may want to consider waiting through one more set of batteries before trying lithium or other emerging technologies. Superior technologies are coming, and prices will drop as PV module prices have dropped in recent years, but we’re not there quite yet.”