In 2015, world governments under The Paris Agreement committed to keeping global warming within two degrees Celsius of pre-industrial times. This meant increased use of renewable energy and the batteries it depends on, such as solar lights.
Whether you are talking about the solar lights in your garden or portable lamps that you can use indoors, they all have a battery that stores the electrical energy converted by the panel to a direct current for use when the sun goes down. Solar light batteries must be rechargeable to receive and discharge stored electrical energy. You’ll need to replace your batteries every two to four years as they depreciate from the constant recharging cycles. This is why you need to know which batteries best suit your needs. As a general guideline by buyabattery, a top online battery retailer in the UK, the new batteries should always have the same voltage as the old ones.
Using solar light batteries has several advantages. For one, they do not rely on the electricity grid to be recharged, thus offering you energy independence. They also offer a clean, less expensive, and quiet energy source.
The best batteries for your solar lights are rechargeable NiMH (Nickel Metal Hydride) batteries and NiCad (Nickel Cadmium) batteries. Although you can use regular alkaline batteries for a short time, they will not last and can damage your light if they leak.
To establish which solar light batteries currently work the best, we tested over 20 popular batteries. We included alkaline, Li-on, NiCad, and NiMH batteries in our test. We used price, life duration (cycles and years), capacity (milliamperes per hour-mAh), storage life (years), and working temperatures (°F) criteria. Below is a list of the best of what we found.
Best overall: Panasonic Eneloop AA 2100 Cycle Ni-MH, 2000 mAh
Things we liked:
✓ Keeps the light on for 8 hours.
✓ Can go for close to 6 years before needing to be replaced.
✓ It works well at low temperatures.
Things we didn’t like:
✘ Needs to be used with a suitable charger
✘ A bit expensive.
The Panasonic Eneloop AA are NiMH batteries, meaning they have a higher capacity than most batteries and will deliver consistent power performance. They have a phenomenal 2,100 recharge cycles, which means they’d last six years before they need to be replaced. This means they have one of the most extended lifespans of batteries on the market.
The batteries arrive pre-charged, so you can establish right away they work. We tested them during a frigid week in winter, and we attested they worked well in shallow temperatures. When recharging them before installation on the light, they do not seem to work with some of the chargers, but they pair well with Eneloop chargers.
Things we liked:
✓ Can run a light for up to 12 hours
✓ Will not leak.
✓ Perfect for outdoor use in freezing or hot temperatures.
✓ Built with high-quality materials.
Things we didn’t like:
✘ Too fat and may not fit in some battery compartments
The price of the pack of four Tenergy rechargeable AA batteries is fair. However, these batteries’ best feature is the high capacity of 2,800 mAh, which can keep the lights on throughout the night, making them very reliable, and are an excellent buy for use in emergencies. These batteries are well-built to withstand harsh environments and are not affected by extreme weather. We were happy that people who had used the batteries for years confirmed the manufacturer’s assertion that they have a long lifespan and will not leak.
The only drawback with these batteries is that they have a wide diameter, so although they fit snugly in lights, they may not fit in or can easily get stuck in some battery compartments.
Best recycled material use: Energizer AA Rechargeable Batteries
Things we liked:
✓ Powers light for 7 hours
✓ Have a lifespan of 5 years.
✓ Work well at temperatures of -4°F.
✓ Made from 4% recycled material
Things we didn’t like:
✘ Shelf storage is limited to 12 months.
✘ Poor performance at temperatures above 86°F.
Several things about these Energizer batteries stand out, especially their long 5 years lifespan thanks to the 1,500 recharges; their high capacity enables them to power lights for seven long hours and the fact that the company uses 4 percent recycled battery material to make new ones. In our experience, these batteries held up in freezing weather and have a sturdy build, making them some of the most reliable batteries.
They are leak-proof, but several users complained that they received the batteries without any charge, perhaps because of the short 1-year shelf life. However, these batteries don’t hold up very well in hot weather and are also quite pricey.
Best budget pack: Amazon Basics AA Rechargeable Batteries
Things we liked:
✓ Affordable
✓ Lasts up to 8 hours per night
✓ Long 3-year battery life
Things we didn’t like:
✘ Short 2-year shelf storage life
The Amazon Basics rechargeable batteries are a set that will surprise you with between 6 to 8 hours of light every night. The 16-battery pack has the best value, which is just the correct number if you have several solar lights and other devices that use AA-size batteries. Overall, this pack offers the best balance between price, capacity, and durability and will last 3 years.
However, we did not like their relatively short storage life. We also had challenges charging them during our test, so although the batteries charged without any issues when used in the solar lights, they seem to be limited in the types of chargers you can use—as a general rule, avoid using super-fast chargers with these batteries.
Best for extreme cold weather- Tenergy AA Rechargeable Battery NiCad
Things we liked:
✓ Can work in temperatures of well below-4°F.
✓ Great pricing
✓ Built with quality materials.
Things we didn’t like:
✘ Average 5 hours of light
✘ Short lifespan of 1.5 years.
✘ Battery contains cadmium, a highly toxic metal.
Tenergy NiCD batteries are some of the few solar light batteries that are genuinely cold weather capable, as they can withstand temperatures as low as -40°F. Unlike some of the batteries on the market, the cold temperature does not change the batteries’ storage capacity. The batteries are reliable in extreme weather and valuable in your lights during the icy months.
Given the preceding alternatives, we were impressed by how well-priced the batteries are. Although they have a short lifespan, it all works to be almost the same amount of money you’d on averagely-price rechargeable batteries over time.
However, the Tenergy NiCaD batteries are not expected to exceed one and a half years of daily use and recharge. Because of this, it is recommended only to get them if you live in an area with extreme weather, as this is where they shine.
Best for hot weather-Brightown Rechargeable AA Battery
Things we liked:
✓ Long hours of light—up to 12 hours
✓ Affordable
Things we didn’t like:
✘ Not for cold weather.
These Brighton AA batteries are best for hot weather for several reasons. First, they have a rated capacity of 24,000mAh, giving 12 hours of power overnight. This exceeds most of the other batteries on the market. They are also reasonably priced, meaning if you live in a hot location, you’ll not need to worry if the solar light will go on at night, nor how much it will cost to replace them once they expire in three years.
However, during our test, the batteries needed a full day of solar charging. They did not hold up very well to extreme winter conditions, so we concluded they are only suitable for hot weather despite their high capacity.
What to Look for in Solar Light Batteries
The following are the primary considerations to look out for before buying a solar light battery:
Battery size
Although most solar lights use AA-size rechargeable batteries, confirm what your lights use before purchasing.
Battery type
Nickel Metal Hydride batteries (NiMH) are the most popular solar light batteries and are considered the safest.
Battery Capacity
The battery capacity ranges from 600 to 2,800 mAh, which refers to how long a battery can produce electricity in milliampere-hours (mAh).
Memory Effect
NiMH batteries charge to total capacity, but nickel-cadmium (NiCad) batteries reset their charging capacity to the last charging level, which lowers their charging capacity.
Disposal
Though safer than Nickel-cadmium batteries, NiMH batteries should also be disposed of in designated stations and not sent to landfills.
Price
Consider the price of solar light batteries in tandem with other factors such as charge cycles, capacity, and warranty.
Warranty
Most manufacturers will offer a minimum of a 1-year warranty, and rarely will you get a 3-year warranty.
FAQ Section
Can I place or use NiMH and NiCad batteries together?
Do not place or use NiMH batteries together with NiCad batteries. This is because they discharge differently and may leak as a result of being placed together, leading to the release of dangerous chemicals or causing damage to your solar light.
Will any rechargeable battery be compatible with my solar lights?
No, not every battery will work properly with every solar light. You’ll need to check the solar light battery compartment, its product manual, and the batteries that came with the light or do a search online to establish which batteries are compatible with your solar lights.
Can I use regular AA batteries in the solar lights?
Yes, you can use regular alkaline batteries in your solar light for a few days. However, they will die quickly, and you risk damaging your light if you leave them in for a long time and let them leak. Solar lights are designed to be used with rechargeable batteries-the panels capture solar energy, which is then stored in rechargeable batteries.
How different are solar rechargeable batteries from regular batteries?
There is not much difference in terms of size. However, the two types of batteries differ in how they are charged, with solar rechargeable batteries using solar energy, while regular batteries are disposed of after they get exhausted. Solar batteries may also be specially made to withstand and work in severe weather conditions, especially lower temperatures during winter.
How do I install rechargeable batteries in the solar light?
Each light model is different, so the best way to do it is by referring to the user manual and following simple instructions.
How long do solar light batteries last?
Solar light batteries last anywhere between 1 year and six years, depending on the number of charge cycles specified by the manufacturer. These range between 500 and 2,000+ times. The higher the number of cycles, the greater the number of years it will last before it finally dies and needs to be replaced.
Where can I purchase solar light batteries?
You can get these batteries from home improvement stores and hypermarts like Walmart. You can also order from the manufacturer’s stores online or from Amazon.
How do I know that my solar light battery is dead and needs to be replaced?
Your solar light battery is dead if the light does not turn on at night but does when you test it with a regular battery. It is also likely that the battery has come to the end of its lifespan if it has exhausted the number of recharges started by the manufacturer.
