It’s no secret that, with the current energy challenges worldwide, more and more homeowners and businesses want energy independence. This means the demand for energy storage is growing, and solar batteries are booming. But batteries are expensive and need periodic maintenance to keep them running at peak performance.
This guide covers everything you need to know about solar battery maintenance. We’ll discuss the different types of batteries, the science behind how they degrade, and the best practices to fight degradation.
We’ll show you how SiteCapture’s solar field operations software can streamline the whole process—from scheduling maintenance to keeping accurate records.
The solar battery industry is booming
Remember when solar batteries were a luxury? That’s no longer the case. Homeowners and businesses are demanding energy independence and blackout resilience. That means energy storage is becoming standard and an increasingly important part of the solar sales process.
In fact, according to Bloomberg New Energy Finance, in countries like Germany, eight out of 10 new residential solar PV installations in 2023 included solar batteries.
While the figures in the US aren’t as impressive—only 15% of new home solar power systems installed in 2023 included batteries—the market is growing fast.
Research by Wood Mackenzie found almost 40,000 new solar + storage installations in the first quarter of the year, nearly 25% of all new systems installed in that period.
That’s a lot of batteries that need to be kept in top shape.
Why solar battery maintenance matters
Proper maintenance keeps solar batteries running efficiently, helps prevent premature failure, and saves both you and your clients money in the long run. Regular solar inspection plays a key role in catching issues early and keeping systems performing at their best.
The numbers speak for themselves.
For example, properly monitoring and controlling a lithium-ion battery’s depth of discharge (i.e., how much of the capacity you drain every cycle before charging it again) can lead to a 25X cycle life difference, as this data from Battery University shows.
Depth of Discharge(DoD) | Discharge Cycles |
100% DoD | ~600 |
80% DoD | ~900 |
60% DoD | ~1,500 |
40% DoD | ~3,000 |
20% DoD | ~9,000 |
10% DoD | ~15,000 |
How does this impact your customer’s bank account?
One study published in Energy found that effective state-of-charge control can save money and improve the battery system’s value by 30%.
The science behind solar battery degradation
Before we dive into the how-to, let’s discuss the “why.” Different types of solar batteries—lead-acid, lithium-ion, and redox flow—naturally degrade over time, whether used or not.
However, each type of battery has a particular degradation mechanism. Here’s a quick look at how each battery type degrades:
Lead-acid battery degradation
Lead-acid batteries (LABs) suffer from several degradation mechanisms:
- Grid corrosion: The lead grid supporting the active material corrodes over time, reducing conductivity and eventually leading to grid failure.
- Sulfation: Lead sulfate crystals can form on the battery’s plates, even during storage, especially if the battery is left completely drained for a long time. This sulfation reduces the battery’s capacity.
- Stratification: The acid concentration in the electrolyte can become uneven, with denser acid settling at the bottom. This leads to uneven charging and discharging and reduces battery life.
- Active material loss: The active material on the plates can shed or become less active with repeated charge and discharge cycles.
- Positive grid growth: During charging, the positive grid can expand, leading to stress and eventual failure.
- Water loss: Flooded lead-acid batteries need water to let ions move around. They can lose water through gassing during charging, especially at high temperatures and overcharging conditions.
Lithium-ion battery degradation
Lithium-ion batteries (LIBs) degrade through completely different mechanisms compared to LABs.
- SEI layer growth: LIBs have a thin solid electrolyte interphase (SEI) layer that protects the anode. This layer grows slowly even when the battery is not in use, consuming lithium ions and reducing capacity.
- Lithium plating: Under certain conditions, lithium can form little metallic, needle-like dendrites that extend from the anode to the cathode, leading to capacity loss and a possible short circuit, as shown in the image below.
- Electrolyte decomposition: Most LIBs have an organic electrolyte that can decompose over time, especially at high temperatures. This leads to byproducts like flammable gasses that can hinder performance and cause fires.
- Structural degradation: The repeated expansion and contraction of the electrodes during charging and discharging can cause mechanical stress and cracking.
Redox flow battery degradation
Redox Flow batteries (RFBs) are quite different from LABs and LIBs, and so is how they degrade:
- Electrolyte degradation: The electrolyte can degrade over time due to side reactions, cross-contamination between electrolytes, and impurities.
- Membrane degradation: These batteries have a membrane separating the two electrolytes, which can degrade over time, leading to increased crossover and reduced efficiency.
- Pump degradation: Flow batteries use pumps to circulate electrolytes between the tanks and the electrochemical cell. Pump damage can reduce flow rates, electrolyte leakage, and other problems.
General solar battery maintenance procedures
Regular maintenance, starting from proper battery installation techniques, can slow down battery degradation and keep batteries working longer. However, because each battery type degrades differently, each has unique maintenance requirements.
That said, you can take a few preventive measures regardless of the battery type:
- Regular inspections: During regular inspections, visually inspect your client’s system for signs of damage, such as swelling, leaks, corrosion, cracks, or loose terminal connections.
- Cleaning: Keep the battery clean and free of dust and debris to prevent corrosion and improve heat dissipation.
- Tighten connections: Periodically tighten all battery connections, including the terminals, cables, and connectors. Loose connections can lead to resistance and heat buildup, damaging the battery.
- Ventilation: Ensure adequate ventilation around the battery to prevent overheating.
Maintaining the charge controller
All solar battery systems come equipped with a charge controller that takes the raw power from the solar panels (and, possibly, from the grid) and converts it to the voltage and current the battery needs. If the charge controller goes haywire, it can lead to battery damage, electrical fires, or explosions.
Here are some ways to maintain this critical piece of equipment:
- Monitoring: Using the built-in display or a connected monitoring system, track key metrics like charging current, voltage, and temperature. Doing so can help you identify problems early.
- Firmware updates: Manufacturers often release firmware updates for charge controllers to improve performance and address bugs. Make sure your charge controller’s firmware is always up to date.
- Testing: Periodically test the charge controller’s functionality by simulating different charging conditions or using specialized testing equipment to ensure it’s working correctly.
Lead-acid solar battery maintenance: Keeping the old faithful running smooth
Lead-acid batteries may not be the newest kid on the block, but they’re still a workhorse in the solar industry. Two main types of lead-acid batteries exist: flooded lead-acid (FLA) and sealed lead-acid (SLA). Both need regular attention but in different ways.
Flooded lead-acid battery maintenance
FLAs are the old faithful of the battery world and the go-to solution for starter batteries and early solar energy storage. They’re cheap and tough, but they need a bit more attention than other types. Here’s the rundown:
- Electrolyte levels and acid concentration: Measure the sulfuric acid’s specific gravity using a hydrometer and add more acid or distilled water to maintain the right concentration and volume.
- Terminal cleaning: Corrosion can build up on the battery terminals, reducing performance. Clean them using a battery terminal cleaner brush, baking soda paste, and distilled water.
- Equalization charging: This helps prevent uneven charging and sulfation, which can shorten battery life. It involves slightly overcharging the battery to ensure all the cells are fully charged.
Sealed lead-acid battery maintenance (AGM and Gel)
Sealed lead-acid batteries, including AGM and Gel types, are often called “maintenance-free.” But don’t let that fool you—they still need some looking after.
While SLAs don’t require checking electrolyte levels or specific gravity, you still need to monitor charge levels. Overcharging can damage these batteries. Ensure your charge controller works correctly and keeps the charge level within the recommended range.
Lithium-ion solar battery maintenance: The powerhouse of modern solar
Business Wire reports that lithium-ion technology is the fastest-growing type of solar battery, accounting for as much as 85% of all new solar energy storage capacity. According to Fortune Business Insights, over half of that energy storage (53.4%) went to commercial solar projects, and most of the rest went to residential installations.
According to GMI, the market is growing at a lightning-fast 15.2% rate and will reach a staggering $258 billion by 2032.
So, it’s safe to say that learning LIB maintenance is critical for solar installers.
NMC Lithium-ion battery maintenance
When we talk about lithium-ion batteries, we often mean the more common type that uses a Nickel Manganese Cobalt (NMC) chemistry. These batteries require less maintenance than their lead-acid cousins, but they still need some attention to keep them running at their best:
- Battery management systems (BMS) calibration: Most LIBs have a built-in BMS that monitors and controls the battery’s operation, protecting the battery from overcharging, over-discharging, and extreme temperatures. Over time, the BMS may become misaligned, requiring calibration. Battery University recommends performing BMS calibration every three months of continued use or 40 particle charge/discharge cycles.
- Checking charging and discharging: Avoid completely discharging NMC batteries, which can shorten their lifespan. Also, be mindful of the depth of discharge (DoD)—how much of the battery’s capacity you use regularly. Shallower discharges generally lead to longer battery life.
Lithium-iron phosphate (LFP) battery maintenance
LFP batteries are a type of lithium-ion battery with some advantages in terms of safety and lifespan. The good news is that they generally follow the same maintenance guidelines as other lithium-ion batteries. So, keep an eye on that BMS, monitor the temperature, and avoid deep discharges.
Flow battery maintenance: The long-haul champions
Flow batteries are built for long-duration energy storage and can handle frequent charge and discharge cycles. They’re not as common as lead-acid or lithium-ion batteries—according to the Journal of Power Sources, the industry installed just 0.25 GWh of flow battery storage capacity in 2019 compared to 8.8 GWh of LIBs.
However, they’re gaining traction.
P&S Intelligence expects the flow battery market to grow almost 10% annually from $401.2 million in 2023 to $759.4 million by 2030. So, if you’re a solar installer and haven’t yet installed a flow battery, you probably will soon.
These batteries have their own unique maintenance needs:
- Electrolyte monitoring and replacement: Flow batteries use a liquid electrolyte, which you must monitor and replace periodically.
- Regular inspections: These batteries have many components, like pumps, tanks, pipes, and membranes. You must check them frequently for leaks, cracks, and other signs of wear and tear.
Flow batteries can be more complex than other types, so following the manufacturer’s maintenance guidelines is crucial.
Modern tools for solar battery maintenance
You’ve got enough to worry about without babysitting batteries all day, but technology can help. Powerful tools exist that can make solar battery maintenance easier and more efficient.
Advanced monitoring systems for solar batteries
Remote monitoring systems let you check on your clients’ battery systems from anywhere, anytime. These systems track key metrics like voltage, current, temperature, and state of charge and sync them to the cloud for global access.
Remote monitoring systems make solar battery operation and maintenance easier by:
- Catching problems early
- Optimizing performance and extending battery life
- Reducing truck rolls and allowing you to prioritize service calls
SiteCapture can integrate seamlessly with many advanced monitoring systems through custom APIs or Zapier.
These integrations allow you to access your customers’ battery data, schedule maintenance, and generate reports all in one convenient place.
Documentation and reporting tools
We know you’d rather be on the roof than behind a desk, but good documentation is essential. It’s not just about keeping your paperwork organized. It’s about protecting your business and clients. This is why:
- Proper documentation is crucial for maintaining warranty compliance.
- Accurate records help you track battery performance over time and identify trends—good or bad.
SiteCapture makes it easy to document your maintenance activities on the field, generate professional reports, and keep everything organized.
Boosting performance and client satisfaction
Solar battery maintenance pays off in the long run. It’s about more than just keeping the lights on; it’s about building a reputation for quality and reliability.
Proper maintenance extends battery systems’ life, saving you and your clients money. Proactive maintenance also helps optimize battery performance and reduce downtime, resulting in happier customers and fewer service calls.
SiteCapture helps you deliver a better customer experience around energy storage system maintenance. With professional reports, efficient communication, and integrations with remote monitoring systems, you and your solar clients will have peace of mind.
This focus on delivering a better customer experience, from initial installation through ongoing maintenance, is a hallmark of successful solar businesses who often utilize comprehensive platforms like a solar CRM software to manage the entire customer journey.
Schedule a demo now with SiteCapture to keep those batteries running strong and keep those customers smiling.
