How do I know if my battery is degrading?

Most batteries come with an app that shows how much energy the battery stores and delivers. Signs of fading include: the battery running out earlier in the evening than it used to, with similar household use the app showing less usable energy than when it was new error messages, or the battery limiting output in hot weather If you are worried, contact your installer first. Under Australian Consumer Law, the installer or retailer is responsible for the installation and the manufacturer for the equipment.

LFP or NMC: which lasts longer?

Most home batteries now use lithium iron phosphate (LFP) cells, which are known for stability and long cycle life. CSIRO's guide lists LFP and the older nickel manganese cobalt (NMC) chemistry with similar ranges of 3 to 15 years and 3,000 to 6,000 cycles. In practice, temperature, sizing and how the battery is used matter more than chemistry alone.

What happens when a battery reaches the end of its life?

At the end of its life, a battery holds noticeably less energy but usually still works. Many owners keep using it, or add a second battery. Recycling options for home batteries are still developing. The national B-cycle scheme does not accept home energy storage batteries. The Queensland pilot found most end-of-life batteries end up stored at installers' premises. Recycling capacity exists in Australia, but it costs money, so ask your installer about collection when the time comes.

Most Reliable Solar Battery Brands for Long-Term Storage (2026)

How Long Do Solar Batteries Last?

Most home batteries last 10 to 15 years and are warranted to 70% capacity at 10 years. What the warranties mean, what shortens battery life and how to make it last.

Batteries & Storage

Published11 November 2026

Reading time6 min

Most home solar batteries sold in Australia today are expected to last 10 to 15 years. Manufacturers usually warrant them for 10 years, promising the battery will still hold at least 70% of its original capacity at the end of that time. A battery does not stop working when the warranty ends. It gradually holds less energy.

How long do solar batteries last in Queensland?

The Queensland Government puts a home battery's life at around 4,000 to 6,000 cycles, which it equates to about one cycle a day for 10 to 16 years. CSIRO gives a similar range of 3,000 to 6,000 cycles for the two main lithium chemistries.

Real-world data supports this. A Queensland Government-funded pilot that collected end-of-life household batteries found they were lasting longer than first predicted, with typical lifespans approaching ten years for the older generation of batteries it studied. Very few had actually reached end of life, and many owners added a new battery rather than replacing the old one.

What does "70% after 10 years" mean?

Battery warranties have two parts:

A defects warranty, covering the battery failing outright, usually for 10 years.
A performance warranty, promising the battery will still store a minimum share of its original usable energy after a set time.

For current home batteries from Tesla, Sigenergy, BYD and Alpha ESS, the performance warranty is 70% of the original usable energy at 10 years. So a 13.5 kWh battery should still store at least 9.45 kWh at year ten. Gradual loss above that line is treated as normal wear and is not a warranty claim.

What is a throughput limit?

Many warranties end at 10 years or after a set amount of energy has passed through the battery, whichever comes first. That amount is measured in megawatt-hours (MWh).

Sigenergy SigenStor: 70% at 10 years or a throughput limit that depends on the module size, for example 29.64 MWh for the 8 kWh module in Sigenergy's May 2026 warranty. An optional extension takes the warranty to 15 years.
BYD Battery-Box Premium: 70% at 10 years or a throughput limit that depends on the model.
Alpha ESS SMILE: 70% at 10 years, provided throughput stays below 3.12 MWh per kWh of usable capacity.
Tesla Powerwall 3: 70% at 10 years with unlimited cycles for solar self-consumption, time-based control and backup. For other uses the limit is 37.8 MWh.

Across these brands the limits work out at roughly 2,800 to 3,800 full charge and discharge cycles. A household cycling its battery once a day would use about 3,650 cycles in ten years, so a battery that is worked hard can reach its throughput limit before year ten. When comparing batteries, look at the throughput figure, not just the number of years.

What shortens a battery's life?

Heat

High temperatures speed up wear. Sigenergy's warranty notes that service life is related to working temperature and recommends 10 to 30°C. Tesla says Powerwall 3 may reduce its output above 40°C. In Queensland, where a battery sits matters.

Where it is installed

The Queensland Government and CSIRO both advise keeping batteries out of direct sun, away from walls that bake in the afternoon, and somewhere ventilated. A garage is often ideal. Avoid unshaded metal sheds.

How deeply it is discharged

Running a battery completely flat can damage it and shorten its life. Modern batteries protect themselves with a reserve, but settings that keep a small buffer help.

How hard it is cycled

More cycles means more wear. Joining a virtual power plant can add extra cycles. The Queensland Government lists faster battery wear as a possible drawback of VPPs, so check how your warranty treats VPP use before signing up.

Staying online

Tesla, Sigenergy and BYD all require the battery to stay connected to the internet for the full warranty. Sigenergy cuts its warranty to five years if the battery is offline for more than a year. Tesla guarantees at least four years if a Powerwall is kept offline.

How to get the longest life from a battery

Choose a battery sized for your evening use so it is not worked to empty every night. Our guide to choosing the right battery storage covers sizing.
Install it in a shaded, ventilated spot, ideally a garage.
Keep it connected to the internet so firmware updates and the full warranty apply.
Read the warranty for throughput limits and any conditions on VPP use.
Have your system checked periodically by an accredited installer.

For ways to get more from the battery day to day, see how to maximise solar battery efficiency.

Frequently asked questions

No. Some datasheets quote 10,000 cycles, but that figure usually comes from the cell manufacturer's laboratory tests. It is measured under ideal conditions, at 25°C with gentle charging, until the cells fall to 60% of their capacity. It describes the cells, not the warranty on the battery you buy. The warranty terms are the better guide to the life you can rely on.