Across the country, solar batteries are emerging as a popular addition to solar panels. They increase solar self consumption and help save money on electricity bills. The excess energy stored can be used when the sun is no longer shining or in a power outage. There are different types of batteries including lead acid, lithium-ion, nickel cadmium and flow batteries. Understanding the best solar battery for panels is crucial for solar panels to reduce reliance on the grid and minimise energy costs. To uncover the best battery for your purposes, consider factors like battery type, energy consumption, efficiency and cost.
What is a Solar Battery?
A solar battery is an energy storage system that stores excess energy made by solar panels to be used when the sun is no longer shining. The solar panels create electricity to be stored in the battery. They convert the sunshine to electricity via a photovoltaic process. Solar panels can only produce electricity when the sun is shining and without a battery, the excess energy is sent back to the grid. With a solar battery that issue is solved as any excess energy is stored in the battery to be used when there is no sunlight in the evening or on low sunshine days like when there is a lot of cloud.
Types of Solar Batteries
There are four types of solar batteries that can be connected to solar panel systems. Each has their own unique features making them ideal for different solar systems. The main types of solar batteries are lead-acid, lithium-ion, nickel-cadmium, and flow.
- Lead-acid batteries: The technology behind lead-acid batteries has been around for over 100 years and they still continue to be used today as they are reliable and cheap to produce. Lead-acid batteries use a chemical reaction between sulfuric acid, lead and water to store electrical energy. This older technology means that lead-acid batteries are not as advanced as other systems. Often these batteries are bulkier and require high levels of maintenance for continued operation. When used consistently, they only have a lifespan of about 5 years. While they are less expensive than other solar battery technologies, they are also more difficult to use, higher maintenance and have reduced lifespan.
- Lithium-ion batteries: Lithium-ion is the most popular solar battery technology for energy storage due to their longevity and high efficiency. The technology used in lithium-ion batteries is similar to those used in smart phones as they store and release energy through the movement of the lithium-ions between two electrodes. Lithium-ion technology has revolutionised energy storage for solar batteries and made it a practical choice for residential and business use. Lithium-ion batteries are lightweight, compact and low maintenance. Depending on their usage, they have a potential lifespan of 10 to 15 years. They are the most expensive of the solar batteries with costs reaching as much as $15,000 .
- Nickel-cadmium batteries: This battery technology is not used in residential applications as often as lead-acid or lithium-ion batteries. Nickel-cadmium is more suitable for large scale applications, or those that demand high durability in extreme conditions. Most often a nickel-cadmium battery is used in backup systems for hospitals, aircraft or data centres. They are not used in homes due to the high toxicity of cadmium and prevalence of memory effect which reduces capacity.
- Flow batteries: The technology of the flow battery is unique as it uses a liquid electrolyte to flow between the two chambers of the battery. This new technology has not yet entered the residential solar storage market and is mainly aimed at large scale energy storage. The main advantage over lithium-ion batteries is their increased safety and long lifespan. However, flow batteries are expensive with prices far exceeding lithium-ion batteries. They are also quite large and require considerable space.
How to Choose the Right Solar Battery
When choosing the right battery for solar panels, you will need a battery that can store enough energy to meet the demand when the sun is no longer shining. Consider factors like the type of battery, capacity, efficiency, and AC/DC coupling in your decision making process.
Battery type
The type of battery has a big influence on the right one for a solar system. Most homes and businesses will err towards lithium-ion batteries as they boast high energy efficiency and longevity. The relatively new technology is ideal for energy storage although they do have a high price tag. Lead acid batteries, on the other hand, are more affordable so great for budget conscious individuals or those in rural and off-grid households. For residential purposes, flow and nickel-cadmium are not the best choice as they are more suitable for larger scale applications.
Energy consumption
To determine the features and size of solar battery you need, look at your daily energy consumption. The purpose of the solar battery is to store enough energy so it can be used when the sun is no longer shining. Daily energy consumption is a good indicator of how big the system needs to be to meet your electricity demands. High energy consumption suggests you will need a large solar battery to maximise self consumption. When looking at electricity consumption, take into account future needs for energy which may increase or decrease in time depending on your circumstances.
Capacity
The capacity of a solar battery is a measure of the amount of energy it can store, measured in kilowatt hours (kWh). The average capacity of a solar battery for residential purposes ranges from 5kWh to 13kWh. Typically, a 10kWh solar battery is large enough to power an average home for 24 hours if necessary.
Efficiency
The efficiency of solar batteries is the percentage of energy it can store and then use. A high efficiency solar battery like a lithium-ion battery loses less energy during the charging and discharging cycle which means more electricity delivered to the household.
AC/DC coupling
AC and DC coupling refers to how the solar battery is connected to the solar system to convert DC electricity to AC electricity for use in homes. When installing a solar battery take into account whether you want AC or DC coupling as each has their own advantages and ideal applications. As a rule, if you are adding a battery to an existing solar system, AC coupled batteries are best. However, for new solar systems where the solar system and battery are being installed together, DC coupling is preferable.
Warranty
Take into account the solar battery warranty which states how long the battery will work in terms of years, cycles and energy throughput. Different batteries have different warranty times. A lithium-ion battery, for example, has a warranty period of about 10 years but a lead-acid battery is half that time.
Cost
Solar batteries are a significant investment and often have varying prices. Consider cost when choosing the right solar battery but be aware that less expensive versions may not have the longevity of energy production of higher end systems. If you focus on the cheapest battery, you may end up with a battery that is too small and is unable to store the amount of electricity you need. A cheaper battery may also be unreliable and low quality which will end up costing more in the long run.
Reasons to get a Solar Battery
Solar batteries allow you to store surplus electricity to be used at a later date. With this in mind, there are a range of reasons to add a storage system to your solar panels. These include:
- Provide backup power: These are the ultimate system for providing backup power. Solar batteries store energy created by the solar panels for use when the sun is no longer shining. As a backup power solution, solar batteries provide power to lights and appliances if the main power source is down.
- Store excess energy: As a system to store excess energy, a solar battery makes the most of the energy made by the photovoltaic effect of the solar panels. This energy would be sent back to the grid without the addition of a solar battery.
- Reduce electricity bills: With less reliance on the grid and less need to buy electricity from a provider, energy bills will be significantly reduced. Provided the system is the right size for your energy needs, bills can achieve energy independence.
- Environmental benefits: Solar energy is a renewable source with no reliance on fossil fuels. This pure energy source is not made with fossil fuels like gas or coal. It reduces the amount of carbon emissions from power plants and is much better for the environment..
- Increase property value: The addition of solar batteries can help to increase property value. According to studies, 60 per cent of those looking to buy a home would pay more for one with solar panels and a solar battery.
Rebates and Incentives
Rebates are offered by the government to cover all or part of the upfront cost of a solar battery. In July, 2025, the federal government launched the Cheaper Home Batteries Program to help more people install batteries. It means you can now get an upfront rebate when installing a solar battery. With this scheme, you can save 30 to 40% off the cost of the home battery system. A typical 10kWh solar battery should receive a $3,300 rebate which is applied to a quote as an upfront discount.
To claim the rebate, the solar battery will need to fulfill these requirements:
- The battery must be installed after 1 July 2025
- Be installed alongside rooftop solar panels
- The battery must have a nominal capacity of 5–100 kWh
- It must be Clean Energy Council (CEC) approved
- Solar batteries must be fitted by an accredited installer
- Can only be claimed once per property. If you own own multiple properties, there are separate discounts for each.
How a Battery and Solar System are Integrated
Solar batteries are integrated to a solar system by either AC or DC coupling. These two methods of installation to an existing solar system must be carried out by an accredited installer.
- DC coupling and installation: This installation requires a hybrid inverter for the solar panels and battery. A hybrid inverter combines the functions of a solar panel inverter and battery inverter into one unit. This inverter converts the DC electricity from the solar panels or battery into usable AC electricity for the home.
- AC coupling and installation: Unlike the DC coupling system, the AC coupling requires two inverters – a solar inverter and a battery inverter. The solar inverter converts the DC electricity in the panels into AC electricity. The second battery inverter converts this electricity back to DC electricity to charge the battery as well as converting it back to AC for supplying power to the home.
Solar batteries are an excellent addition to a solar system, allowing you to save more money on electricity bills and become less reliant on the grid. With the introduction of the new solar battery rebate, installing a solar battery is much more affordable. Contact the team at Tasmanian Safer Solar for more information on the best battery for solar panels.
1300 655 808
