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How Long Do Solar Batteries Last For?

How Long Do Solar Batteries Last For?

Solar batteries come in three main types, each with different lasting times. How long do solar batteries last for comes down to the materials and the quality, with the longer-lasting batteries often being the more costly options.

Different battery types are also generally warrantied for different periods. It’s important to understand the different battery options that you have, and which one might be right for you.

What is a solar battery?

Your solar system is likely producing more energy than you are using moment to moment during the sunny hours of the day.

Solar batteries are designed to store this excess energy for later use, meaning that even when the sun isn’t shining, your home can still make use of your solar panels.

Sams Solar Penrith Sungrow Solar Battery

Different types of solar panel batteries

Lithium-ion

The highest quality and longest-lasting of your solar batteries is lithium-ion. With a warranty period of generally around 10 years or 10,000 full cycles, this battery is good for the long run. So how long do lithium solar batteries last? With proper care and maintenance, it’s not out of the question for this battery to last even up to 15 years.

Salt-water

One step down from lithium-ion batteries are salt water batteries. This battery type will generally be warrantied for around 5 years or 3,000 full cycles. The major advantage of salt-water batteries is that they have the best depth of charge out of any option on the market. This means that they can hold more power in one charge.

Lead-acid

Lead-acid solar batteries are the lowest-priced option, and they are cheap for a reason. They have the shortest lifespan and the lowest depth of charge. They can, however, be a great starter battery for those on a budget, with the understanding that the long-term price may be more since you’ll have to replace it sooner.

Sams Solar Penrith QCells Solar Battery

How long do solar batteries take to charge?

The amount of time your solar battery takes to fully charge will depend on the system’s size, the battery’s size, and your power usage. Batteries will only begin to charge when there is excess power being produced by the system and not being used. Usually, this will happen between the hours of 10-4, when the sun is up but there is little power being used in your home.

With a battery that matches your solar system’s capacity, and is not too big or too small, you will find that your battery will generally charge in a day or two. Once it is charged up to its full capacity, your energy system should be able to support your energy usage throughout the evening and night if your energy usage is fairly conservative. This means that generally you can rely on your battery to cover your day-to-day power usages unless you are using an unusually large amount of power or the weather isn’t in your favour.

When your solar battery does run out, you won’t be left without power so long as you are hooked up to the power grid. You should not expect your power bill to go away completely. There will always be times where you’re using more electricity than your battery is storing, or where the sun is not shining. In winter especially, where you might be using more electricity from the grid and storing less in your battery.

When should I replace my solar battery?

You will need to replace your solar battery before you have to think about replacing your whole system. The panels and inverter in your solar power system will generally have a warranty of around 25 years, wheras the life cycle of your battery will often be around 10 to 15 years, depending on the lifetime of the battery you choose and how frequently it is being used.

The question of how long do home solar batteries last will depend in a large part on the type of battery. A lead-acid battery will need to be replaced after around 3,000 cycles, which equates to around 3 to 5 years, while a Lithium-Ion battery will last around 10,000 cycles, which will pass after around 10 years.

You don’t need to be meticulously keeping track of all this of course. With regular servicing your technician will be able to tell you when it’s time to replace your battery. The technology used in solar batteries, regardless of

the type of battery you choose, is established technology that is well understood. Solar panel lifespans can be a little more difficult to predict because the technology is so new.

How can I maintain my solar battery?

How long do solar batteries last will depend in part on the maintenance it receives. Your solar batteries lifespan can be extended with proper care and maintenance, saving you money in the long-run. The maintenance that your battery needs will depend on the type of battery you have chosen.

If your solar battery is lithiumiion, then it will generally be pretty simple to maintain. They don’t require deep cycling as often as other types of batteries, because they don’t hold memory in the same way that other batteries do. Every 30 cycles is a good cadence to deep cycle your battery.

Sams Solar Penrith Enphase Solar Battery

The major consideration with lithium-ion batteries is temperature. If the ambient temperature goes above around 30 degrees, they will not only hold charge less effectively, but they will also degrade more quickly. Your installer will help you find the right spot in your home to keep your battery temperate, and you also have the option of investing in a battery with a built-in temperature regulation, which will be extremely helpful.

If you have opted for a lead-acid battery, you will need to perform regular maintenance to ensure your battery is performing well. Lead-acid batteries are the same type of battery that powers your car, so just like your car battery, you will need to check water levels, and add distilled water and electrolytes when they get low. It is important to check these levels regularly, but be cautious not to overfill your battery, as that can cause damage of its own.

You will also need to regularly check your cables to ensure they aren’t falling victim to terminal corrosion, which is another issue you might associate with car batteries. If you aren’t prepared to undertake regular maintenance, it might be worth your while to invest in lower-maintenance battery options like lithium-ion or salt-water.

Sams Solar Penrith Residential Solar Battery Installation

What size battery will my solar panel system need?

The size of battery that best suits will depend on two things: your power usage and the size of your solar panel system. How much power your household uses, and when, will impact how much power needs to be stored to cover your energy usage. The Australian average daily power usage is 15kWh, weighted towards the evening.

Since most people are out of the house from 9-5 working, they use only around 35% of their energy during daylight hours, when solar panel systems are producing energy and the rest at night. This means that the right battery will have to hold around 65% of your daily power usage. This equates to around 10kWh of required energy storage.

If you have a particularly large solar system, or you are a household that uses more power than average during the evening, due to having a large family, charging an electric car, or running a business out of your home for example, then a battery that holds 10kWh may not be sufficient.

Additionally, a larger battery might be a better option if you are looking to take your home more off-grid. Especially if you are choosing to no longer be connected to the power grid at all, you will need a battery that can facilitate that, holding around 5 to 7 days of power to cover you during overcast or rainy periods without sun.

In summary

Just like choosing your what solar panels are suited to your circumstance, the same needs to be applied to choosing the type and size of solar battery. By contacting Sams Solar and discussing your energy needs, you can be presented with a choice of Solar Batteries that will suit your budget.