Solar batteries in South Africa are providing an increasingly affordable and sustainable alternative for energy storage. They are providing a welcome boost for the adoption of eco-friendly solar power.

In this article, we offer…

Making solar affordable: 2ndLiFe solar batteries

Our 2ndLiFe batteries are revolutionising the market for lithium-iron solar batteries in South Africa. These batteries are repurposed for use as stationary energy storage systems after use in electric vehicles (EVs).

Ideal as solar batteries, they cost much less than traditional lithium-iron batteries.

They feature automotive-grade (rather than storage-grade) cells – a superior grade for battery performance. They offer exceptional performance and durability.

And they come with a warranty for 10 years or 3,500 cycles, whichever comes first.

Because the batteries are repurposed after use in electric vehicles (EVs), they’re also more environmentally friendly than comparable, new batteries. They’re helping solve a potential waste problem, as more and more electric vehicles are produced and their batteries have to be replaced.

Solar battery prices in South Africa

Even without REVOV’s market-disrupting introduction of 2ndLiFe alternatives, the price of lithium-ion batteries has fallen steadily over the past few decades. At the same time, the technology they use has continued to improve.

The price of solar batteries for sale in South Africa depends on three main variables:

  • brand
  • size
  • type of battery.

Generally, the higher the cost of a battery, the larger its capacity and the longer its lifespan.

Lithium-iron solar batteries are initially more expensive than lead-acid batteries. However, they’re generally acknowledged to be the best solar batteries on the market. They have longer lifespans, so you save money in the long run.

You can compare a range of battery types and prices here. Also, see a comparison of the average cost of a lithium-ion battery versus a lead-acid battery.

In real terms, lithium-iron batteries are more cost-effective

According to a recent price survey, the cost of a particular 2.4 kWh lithium-ion battery (1.92 kWh usable) was R13,000. A comparable lead-acid battery (4.8 kWh but with 2.4 kWh usable) cost R9,200.

However, the cost per year for the lithium-ion battery amounted to just R790.75 – compared to R2,486.49 per year for the lead-acid battery, which lasts for only 3.7 years.

That’s quite a difference. A little over 300%!

REVOV’s 2ndLiFe batteries offer even better cost-effectiveness. They provide the lowest cost per cycle among comparable batteries on the market.

Solar batteries FAQ

Here, we answer a series of commonly asked questions about solar batteries.

What are solar batteries?

Solar batteries are separate components that store the energy produced from solar panels.

The electricity can then be used at a later time. This could be at night, for example, when the panels are no longer producing energy or when there’s an Eskom power outage.

How do solar batteries work?

Solar batteries store energy from photovoltaic (PV) systems. The solar panels absorb energy from the sun, which is converted into electricity. This passes through an inverter so the power can be used in a home or business.

When the electricity isn’t used straight away, a solar battery converts this DC electricity into AC power and stores it, ready for later use. Essentially, solar panels charge solar batteries when the energy they’re producing isn’t used.

What are the different solar battery types?

There are three types of solar batteries – lead-acid, lithium-ion and redox flow batteries.

Lead-acid batteries have been around the longest. Absorbent glass mat (AGM) is the latest lead-acid technology. In an AGM battery, the electrolyte takes the form of a gel paste. The lead acid is absorbed into a fibreglass mat.

AGM batteries are better than traditional flood lead-acid batteries. They’re maintenance free, are sealed (so don’t leak acid or fumes) and they’re very stable. They have a low discharge rate.

Solar batteries lithium-ion are the latest technology in solar batteries. In a lithium-ion battery, lithium ions move from the negative electrode to the positive electrode during discharge and back when charging.

Saltwater batteries are the most environmentally friendly because they don’t use heavy metals. However, they have lower energy density and have to be about twice as large as lithium batteries. They also take longer to charge and discharge.

What’s the best battery for solar power?

Solar lithium-iron phosphate batteries – also called solar LiFePO4 batteries – are the best lithium batteries for solar systems. Their chemistry makes them the most cost-effective option for homes and businesses. They’re safer and less toxic than alternative solar battery types.

A lithium-iron solar battery can easily be scaled. It’s easy to add capacity to an existing installation to meet growing energy needs or to build towards a fully off-grid solar system.

These are some of the qualities of REVOV’s 2ndLiFe LiFePO4 batteries:

  • significantly longer lifespan – in studies, lithium-iron batteries deliver many times the total number of cycles in their lifetimes than lead-acid batteries.
  • higher capacity – lithium-iron batteries take up less space and can charge more appliances.
  • greater efficiency – upwards of 95% of the energy in a lithium-iron battery can be used. For a lead-acid battery, efficiency is typically 80 to 85%. Batteries with greater efficiency charge faster and have higher capacity.
  • greater depth of discharge (DOD) – a lead-acid battery generally has a DOD of about 50% – meaning you shouldn’t use more than half the available kilowatt hours (kWh) from the battery before recharging it. A REVOV lithium-iron battery offers a DOD of about 90%.
  • safer and lighter – lithium-iron batteries are safer and lighter than lead-acid batteries. They can be wall-mounted and are solid. They don’t require maintenance or refills.

Which solar batteries last longest?

Lithium-iron phosphate batteries last longer than any other solar batteries. As an example, REVOV 2ndLiFe batteries are guaranteed for 10 years or 3,500 cycles at one cycle per day, whichever comes first.

As well as lasting longer, lithium-iron phosphate batteries offer the best storage capacity and many times the number of cycles in their lifetimes compared to lead-acid batteries.

What is a second-life EV battery?

A second-life EV battery, such as REVOV’s 2ndLiFe battery, is a lithium battery that was first used in an electric vehicle (EV). It’s then repurposed for a second life as an energy storage solutions for solar power.

Second-life EV batteries are less expensive and more environmentally friendly than new lithium batteries as there is virtually no construction or chemical consumption.

How many solar batteries do I need?

This depends on your goals and requirements. If you want to be off grid, you’ll need more solar batteries than if you simply want backup power for when Eskom fails or to reduce electricity costs to your home or business.

A single 100 amp hour (Ah) battery might suit lower power needs or those at the start of the journey towards full energy independence.

A 200 Ah deep-cycle battery provides the same amps per hour, or capacity, as two 100 Ah batteries connected in parallel (provided the connections don’t add resistance).

A 200 Ah battery gives power for longer and can be less expensive than multiple 100 Ah batteries. Of course, it’s heavier to move around than individual 100 Ah batteries.

At REVOV, we offer 2ndLiFe 100 Ah batteries, the REVOV R100, as well as solar batteries 200 Ah, the REVOV R9, which is ideal for off-grid applications.

Is a 10 kWh solar battery enough to power a household?

Yes, a 10 kWh solar battery, like our REVOV R9, should be sufficient to power an average South African household.

Contact us at REVOV for more information about the best solar batteries in South Africa or to discuss your energy storage needs.