There has been a lot of talk about the use of second-life EV batteries, potentially as a home energy storage solution. This is intriguing, as it offers a dual solution – reducing the waste from EVs and reducing the cost of home energy storage systems. But what’s the deal? Are used EV batteries good for home energy storage? Let’s investigate.
A ground-breaking study
Academics at Newcastle University’s School of Engineering recently released their thoughts on the use of EV batteries for home energy systems in their ground-breaking study – A Study on the Safety of Second-life Batteries in Battery Energy Storage Systems.
They drew on information from 39 organisations in the UK who have experience of using second-life lithium-ion batteries for home energy storage purposes and their findings are both important and intriguing. Essentially, there are two distinct viewpoints that need to be considered.
Safety framework
The first conclusion of the report is that a safety framework would need to be put in place if EV batteries are to be used in home energy storage systems. What’s more, the full history of the batteries should be known and tested professionally before installation. This would rule out the introduction of damaged or potentially dangerous batteries into homes and is a crucial point as far as health and safety is concerned.
The safety of the cells themselves
A number of the organisations contacted for the report announced scepticism about the safety of the cells themselves, arguing that it’s not easy to guarantee the safety of used cells. Some even went as far to say that second-life EV batteries shouldn’t be used in home energy storage systems for this precise reason. This concern highlights the fact that there’s a long way to go if second-life EV batteries can be installed in home energy systems in the future.
The verdict?
Safety is of the utmost importance as far as battery energy storage is concerned. One of the most significant issues facing the safety of EV batteries in energy storage is that the batteries can age at differing speeds, potentially reaching a State of Health (SoH) of 50-60% sooner rather than later, which is regarded as end of life.
It’s very difficult to predict when EV batteries will reach end of life when being run in a battery energy storage system, and the threat of thermal runaway also increases.
In agreement with the report, we would conclude that there’s undoubtedly merit in conducting further study into the possibility of using second-life EV batteries in battery energy storage systems. But safety and proficiency are extremely important, and there’s a long way to go until we can say that it’s safe and recommended to use second-life EV batteries for this purpose.
