More solar energy storage batteries

More products are coming to market all the time. Here’s our take on the best of the rest.

BYD Solar battery storage


BYD (Build Your Dreams) are a large Chinese manufacturer of batteries for major mobile phone brands. They’ve also been researching energy storage for renewables since 2006. Their domestic offering is the MiniES which has 3kWh of useable storage and can be increased to 6kWh with an additional battery. With a product warranty of 5 years and battery warranty for 8000 cycles, this is likely to be a market leader amongst the Chinese offerings.


LG Chem

LG Chem, which is headquartered in Seoul, is the largest chemical company in South Korea.

Why Lithium Ion?

Lithium Ion or Li-Ion, is an alternative battery type to lead acid. Whilst lead acid, or gel batteries remain cost effective options for grid-backup and off-grid systems, lithium ion is fast becoming the chosen option for many PV applications, offering better functionality and longevity.

The life expectancy of a good quality Li-Ion battery far exceeds lead acid even when charged and discharged every day. Equally importantly they have a higher depth of discharge (DOD), allowing you to use more energy before a further charge is needed. Typically, lead acid batteries only have a 50% DOD, meaning they can only discharge half of their energy stored before needing to be charged again. Lithium Ion batteries typically offer a DOD of around 90%. This also means that when comparing Lead Acid to Li-Ion, you need to compare two batteries with the same usable kWh – not the listed kWh size.



SolaX is a Chinese company who have been in the UK inverter market since 2015 with a wide range of inverters suitable for many solar energy set ups. They also have a range of Hybrid inverters that let you connect your solar panels and battery in to the same inverter (DC Coupled).

Being a modular battery, you can start small and add more batteries in the future.  Just be aware that if the range changes then SolaX may not continue to produce the batteries that suit your system.  Unless you have more than one of the batteries then the charge/discharge rate is going to be disappointing too, not even enough to power your kettle and if you have 4kWp then most of your excess will be exported to the grid.