If you’re thinking about getting a home battery (or already have one), you’ve probably wondered, “How long do solar batteries last?”
It’s a fair question. Batteries are a big investment, and if you’re using yours to cut bills, back up your home, or power your place with more renewables, you’ll want to know how long it’ll hold up.
So what’s the real solar battery lifespan? Let’s break it down.
The short answer
Most home batteries, including popular models like the Tesla Powerwall, are built to last at least 10 years, and many last well beyond that with the right conditions and care.
That’s the minimum lifespan most manufacturers guarantee. But in practice, a high-quality lithium-ion battery in a mild Aussie climate can last 12 to 15 years, and sometimes even longer.
The longer answer
A solar battery doesn’t just suddenly stop working one day. Its capacity gradually fades over time - a process called solar battery degradation.
That means your battery will still work after a decade, but it might not store quite as much energy as it did on day one. You’ll still get value from it, but it might charge or discharge a bit differently.
How long your battery lasts depends on a few key factors:
- The number of battery cycles (how often it’s charged and discharged)
- The depth of discharge (how much of the battery you use each time)
- Where the battery is stored (temperature makes a big difference)
- The type of battery chemistry (some last longer than others)
Not all batteries are created equal
Most solar batteries installed in Aussie homes today are lithium-ion – and that’s a good thing. They’re efficient, durable, and can handle thousands of charge-discharge cycles without degrading too quickly.
Here’s how the main types stack up:
Lithium-ion
Typical lifespan: 10-15+ years
Key features: Most common in Australia; reliable and long-lasting
Lead-acid
Typical lifespan: 3-7 years
Key features: Cheaper, but shorter lifespan and lower efficiency
Saltwater
Typical lifespan: 5-10 years
Key features: Non-toxic and recyclable, but less common and still emerging
Warranties vs real-world results
Battery warranties usually last for 10 years, or for a set number of battery cycles (often around 6,000).
Many manufacturers guarantee that your battery will still have around 60-70% of its original capacity by the end of the warranty period. That means you’re still getting storage - just not quite as much as when it was brand new.
In real-world conditions, a well-installed, lightly cycled lithium battery can last well beyond its warranty - sometimes up to 15 years or more.
Battery cycles and depth of discharge
Every time your battery charges and discharges, it completes a cycle. Over time, these battery cycles wear the battery down - just like charging your phone every night eventually shortens its battery life.
But not all cycles are created equal. Using only part of your battery’s capacity (a shallower depth of discharge) puts less strain on it, which helps slow down solar battery degradation.
Most manufacturers recommend keeping your Depth of Discharge (DoD) below 80% to get the most out of your battery over time.
Where you store it matters
Extreme heat and freezing cold can both shorten a battery’s life. That’s because high temps accelerate wear, while cold temps make it harder for the battery to operate efficiently.
If possible, install your battery in a spot that’s sheltered from the elements, like a garage or shaded outdoor area.
When to replace a solar battery
Wondering when to replace your solar battery? The signs usually show up gradually:
- It doesn’t hold as much charge as it used to
- It charges or discharges more slowly
- You’re needing to recharge more often
- Your system sends alerts or flags performance issues
If your battery is still working but underperforming, a replacement might be on the horizon. If it’s shutting down unexpectedly or you’re no longer getting value from it, it’s likely time.
What about specific battery brands?
Most lithium-ion batteries, including popular models from brands like Sungrow, BYD, and others, come with a 10-year warranty and are designed to last well beyond that under normal use. Manufacturers generally guarantee that the battery will retain around 60-70% of its original capacity by the end of the warranty period.
In real-world conditions - especially when installed in a mild climate and not pushed too hard - it’s common to see batteries still performing well after 12 to 15 years. That’s true whether you’ve got a Sungrow, a BYD, or any other quality brand on the market.
Just remember: how long your battery lasts will depend far more on how it’s used and where it’s installed, rather than on the name printed on the side. A battery in a well-insulated Melbourne garage may last a lot longer than one in a sun-exposed Darwin carport. So while brand matters, how you use and house your battery often matters more.
Tips to maximise your battery lifespan
Want to make your battery go the distance? Here’s how:
- Avoid deep discharges - try to stay above your battery’s recommended DoD
- Minimise unnecessary cycling - using automation can help here
- Keep it cool - install it somewhere with mild, stable temperatures
- Choose a quality battery - and check the warranty conditions
At Amber, we help our customers get the most out of their batteries through our SmartShift tech, which automates charging and discharging to help extend battery life, reduce costs, and shift to greener energy.
Smarter batteries start here
If you’re using a quality lithium-ion battery in typical Aussie conditions, you can expect it to last well beyond its warranty - often 12 to 15 years or more.
And when it’s automated with SmartShift, your battery isn’t just lasting longer - it’s working smarter. That means less effort for you, lower bills, and more support for the renewable energy transition.
Keen to take the next step in your battery journey? Contact us today to discuss your options.
