We are often asked about the difference in Lithium and Lead batteries and can spend all day discussing the various benefits / problems with each. When it comes down to it they are both good, but whether you choose Lithium or Lead (or some other chemistry) depends on your project.
A typical Australian home uses around 20kWh of power each day and the average solar system exports about 40% – 60% of its supply to the grid. So you might choose to store this power in a battery and use it to power up your home at night or when there is more power needed during the day than what the sun has to offer.
Lithium batteries are designed to use a fair amount of their battery capacity even up to 90% or more. So you could get a 12kWh battery and use 10kW of it and then it is flat – waiting for its next charge.
Lead batteries are different in that they are designed to use about 15% – 20% of their capacity so if you need about 10kWh each day then you would buy 50kWh of storage. And in some cases you can buy 50kWh of lead storage for the price of a 12kWh lithium battery. And if you were 100% completely Off – Grid this is what you would do. The reason is that there will most likely be times throughout the year (normally June and July) when you might go 2 or 3 days without enough sun to recharge your batteries. So in this case your properly designed system will allow your batteries to be discharged to a lower level – even down to 30% – 40%. In this instance you have an additional 20kWh available to you, whereas the lithium would be dead flat much earlier.
Overall, lead acid batteries are cheaper ($ per kWh of storage) than Lithium but they don’t look as cool and they need more space. If you are looking to be truly self sufficient from the grid then have a look at what the good quality German made, lead acid / or Gel batteries have to offer. If you just want to stop exporting to the grid and start saving that power for your own use later in the day or at night but still don’t mind buying additional power when you need it, then Lithium solution might be the go.
Examples of Gel / Lead acid batteries that we have recently used are BAE, Sonnenshein and Energystore.
Examples of lithium batteries include Enphase, Fronius, Tesla and LG Chem.
Solar and battery storage doesn’t have to be expensive or confusing. National Renewable Group (NRG) specialise in designing and building battery systems for homes and businesses. If you would like any more information please free to comment here, esquire through our website or call us on 1300 858 160 and we will be happy to help you on your solar storage journey.