Diving into deep-cycle batteries
With the ability to provide a stable, reliable power supply over an extended period of time, deep-cycle batteries are the products powering South Africa’s residential and commercial PV systems.
And whilst all these intelligent energy storage solutions can provide much-needed relief from the country’s energy crisis, not all deep cycle batteries are created equally.
In fact, there are two key types of deep-cycle batteries: lead-acid and lithium-ion.
As an installer, it is your job to know the differences between the two, understand which one is best suited to each of your projects, and supply customers with the best possible energy supplies for their needs.
So, if you need to brush up on your knowledge of deep-cycle batteries, keep reading. We are here to tell you everything you need to know about these PV system components and offer a couple of product recommendations from none other than REVOV: a forward-thinking South African PV battery brand.
Comparing lead-acid and lithium-ion models
In lead-acid batteries, negative and positive lead electrodes are immersed in sulfuric acid and water — creating a bond and generating an electrical charge. Because this technology is so well-established, having been invented in 1859, lead-acid batteries come with a relatively low upfront cost.
However, lead-acid batteries have several drawbacks. Firstly, lead-acid batteries must be fully discharged after every discharge cycle and must never be discharged below 50% (meaning end-users only ever get to use half of their battery). This is to avoid sulfation, where crystallised lead sulphate builds up on the battery plates causing longer charging times, excessive heat, shorter battery life, and even product failure.
Moreover, lead-acid batteries require regular maintenance, as water can be lost during the chemical reaction, which must be topped up to ensure it functions as intended. Hydrogen is also released during lead-acid battery operation, which is environmentally damaging and can be unsafe if not stored in a well-ventilated area. Plus, these batteries must be stalled upright to prevent leakage.
On the other hand, lithium-ion batteries work a little differently — using a carbon anode and lithium-ion cathode in place of lead and sulphur. There are numerous types of lithium-ion batteries available, such as lithium cobalt oxide and lithium manganese oxide, but lithium-ion phosphate ones (LiFePO4) are generally considered to be the best.
Whilst these solutions are typically more expensive than lead-acid alternatives, they beat them on many counts. For example, most lithium-ion batteries have a much higher depth of discharge (DoD) providing access to more of the product’s energy supply. They are also much safer and eco-friendly than lead-acid batteries, with good chemical and thermal stability and a non-toxic composition resulting in a lower risk of failure and a longer lifespan. And they can be installed in many orientations…
Choosing the best LiFePO4 solutions
As you can see, lithium-ion batteries (and more specifically, LiFePO4 models) are the ideal choice for installers looking to provide home and business owners with a safe, sustainable energy storage solution that lasts.
There is no need to worry about the price of these premium products, either. REVOV supplies the 11.2kWh R9 and 5.1kWh R100: two cost-effective LiFePO4 models built with repurposed automotive-grade electric vehicle (EV) batteries. Not only does this innovative design choice help prevent high-quality components from going to landfills before their time, but it also brings the carbon footprint of each product well below traditional figures — a win-win for conscious installers.
These low-voltage 2nd LiFe solutions are significantly less expensive than competing batteries, with all the features to be expected from a top-quality product. For instance, these batteries boast an outstanding 100% DoD for optimum efficiency, built-in protection against overcharge, overdischarge, and over temperature, preventing faults, and the flexibility to facilitate convenient wall or rack mounting.
What’s more, all REVOV batteries come with a ten-year warranty. And thanks to their parallel capabilities of up to 15 units, the R9 and R100 are also suitable for a range of PV system sizes, including off-grid, backup, and self-consumption systems.