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Sonnen Battery Information

December 02, 2020

Solar energy is the new normal in the energy industry, especially with the modern trend of environmentally friendly ways of generating electricity. Since solar panels are only powered during the day, it is necessary to own a durable battery to store solar energy. Having an array to store your solar power will ensure you have solar power throughout, be it day or night. Sonnen batteries are among the top quality batteries for solar energy storage worldwide.

Sonnen, also known as sonnenBatterie, was founded in 2010 in German and reached the US market in 2015 and opened its headquarters in San Diego in 2016. Sonnen Battery is one of the most reputable global leaders in the invention of smart home energy storage. Their creation of solar cells has enabled the saving of excess clean energy after sunset.

The components of a home energy storage system vary depending on the company that has produced it. Usually, a self-consumption system has a battery inverter, batteries, a charge controller (DC enabled) or PV inverter (AC coupled), interconnection wiring, and other system components such as relays, bypass switches, and disconnects. The Sonnen battery has most of these components integrated into it, making installation easier.

If you are looking to find a suitable energy storage system for your home, Sun Solar Electric will have all your needs covered. We offer a wide range of solar installations and other services. Our competent personnel will take you through in choosing the best solar energy batteries for your home. We also offer a free consultation. Reach out to us to explore possible solutions for your energy storage needs or solar panels installations.

Sonnen Battery

Sonnen batteries are made of single 2.5kWh (Kilowatt-hour) lithium battery modules linked together in varying capacities ranging from 5 to 15 kWh. LFP models are some of the longest-lasting and reliable cells available.

How Sonnen Batteries Work

Usually, power storage batteries are combined with your solar panels. In most cases, the energy collected by solar panels is in excess and ends up flowing off to the National Grid and is lost. Having solar energy storage will help you tap the excess power and use it later this way, reducing electricity bills.

Sonnen batteries typically store solar energy that is in excess or for use when there is a blackout. There is less energy stored in the mornings since the usage (discharge) almost equals the charging; therefore, your home appliances are powered by the power stored the previous day. At midnight the batteries experience high load since the sun is hotter than in the morning and evening. At the same time, there is limited or no power usage during the day; hence more power is saved. At night, there is no charging, and the energy stored during the day is used to power your nighttime power usage.

Sonnen batteries can be used independently without having to install solar panels. You can then charge them directly with your on-grid power when the charging rates are lower and use the batteries' energy during the day when the charge rates are high. They are installed on your walls or your floor as well as outdoors.

The batteries are connected to your fuse board. Cells directly related to your fuse board are known as AC-Coupled. Once connected, the battery either charges the fuse box or discharges the fuse box.

Features of the Sonnen Battery

  1. Battery Lifespan

Sonnen says their batteries can last up to 20 years. More so, they provide the highest warranty you will find in the market of 10,000 cycles or ten years. The 10,000 cycles are a lot, and the ten year period will sure come first. For the battery to live up to its full potential, you have to keep it in the right conditions guided by the manufacturer. Charge time for the battery varies according to its capacity; for example, a battery with 12kWh takes around three and a half hours. Being a smart battery, when it is fully charged, it will cut off power and direct it to the grid.

  1. Capacity

Capacity is the amount of electricity a battery can store, and it is measured in kilowatt per hour (kWh). The Sonnen battery being a modular system, the Sonnen battery can be expanded as per your requirements. Home energy storage depends on what the homeowner requires. Some home appliances need more power than others; therefore, determining which of the six different size units will be necessary for your home is critical. It is recommended you get a size slightly larger than the one you expect to have room for expansion if you need more energy storage in the future. Get an installation provider near you to get your installation sized to get a fit battery. Sonnen battery is available in the following storage capacity:

  • 2.5kWh

  • 5kWh

  • 7,5kWh

  • 10kWh

  • 12.5kWh

  • 15kWh

Sonnen claims their battery gives an output of 90% of its storage capacity, meaning a battery with 5kWh capacity outputs 4.5kWh. Two or more cells can be stacked together depending on your home’s energy storage needs; for example, you can combine 15kWh with 5kWh to get a 20kWh. This stacking can yield up to a maximum of 45kWh capacity and storage. Sonnen batteries are modular, therefore making it easy to stack them to suit your preference storage capacity as compared to others such as Tesla, which offers one size of 13.5kWh.

  1. Inverter

The inverter in the Sonnen battery has a capacity of 3.3kW output power. This output power may be limited for households where there is high power usage, such as electric car charging. However, for average and minimal power users, this 3.3kW limit does not have any effect. Sonnen batteries that undergo low to average power output have a longer lifespan since the charge/discharge rate is lower compared to battery capacity. The less the cycles a battery undergoes, the longer the battery’s life is prolonged, and it functions more efficiently.

  1. Coupling

AC coupling means that electric energy from your solar panels flows directly to your solar inverter. The inverter then converts the electricity into alternating current (AC). The AC electricity then flows into another inverter, which transforms the power into direct current (DC), which can then be used by your electrical appliances or be stored in the battery. 

  1. Round trip efficiency and DoD

Sonnen batteries all have a DoD of 100% and an 86% round trip efficiency. For instance, if your battery has a 10kWh capacity, it will have a discharge (output) of 8.6kWh.

  1. Chemistry

Sonnen batteries are made of the safest Lithium technology, Lithium Iron Phosphate (LFP or LiFePO4). The LFP battery chemistry is inherently safe and durable for home battery systems; battery cells made of LFP chemistry do not burn, making them suitable for residential use. The LFP technology is the only battery that has components occurring naturally with no heavy toxic metals.

  1. System Intelligence 

With its system intelligence, Sonnen battery ensures that your PV output is optimized through predictive charging. The installed software ensures that all the features of the battery run efficiently. You can also control the system from a smartphone through Sonnen applications. 

  1. Warranty

Sonnen offers customers a warranty of 10 years or 10,000 cycles whichever comes first. The warranty covers all components of your Sonnen battery: the battery modules, all power electronics, energy manager as well as the inverter. For the warranty to be valid, several conditions must be met: the battery must be maintained in well-controlled surroundings. The battery must have an internet connection to receive software updates and maintenance services. If the Sonnen battery is offline and fails to receive updates, then the warranty becomes unguaranteed.

Types of Sonnen Batteries

Sonnen batteries are of two types: the sonnenBatterie Hybrid or All-in-one system and Sonnen ECO suitable for homes with already existing solar installation.

  1. SonnenBatterie Hybrid- All- in- One Battery

This type has an inbuilt solar inverter, charger, and battery. You can have your solar panel connected to the Sonnen battery and get rid of the inverter you had, or if you had not installed a solar panel already, you could opt not to buy one. This hybrid version can work on its own without having to be connected to a solar panel. You can charge it with on-grid power when electricity pay rates are low and use it when pay rates are high or there is a blackout. The hybrid has a maximum of PV solar capacity of 6.4Kw and an inverter power rating of 5.5kW. For large homes or commercial buildings requiring large amounts of power, clusters of sonnenBatterie can be installed; for instance, three 15kWh to give a total of 45kWh.

  1. Sonnen Eco- Modular AC Battery

This type of Sonnen battery has a standard AC-coupled battery that connects directly to your fuse board. It is a modular system of 2.5kWh capacity batteries. It is suitable for those who have already installed solar panels.

Back-up Power

The Sonnen Back-up Box is an additional but optional feature; your battery can still function without the Back-up Box. Its purpose is to allow you to access the electricity stored in the battery during a power cut. The accessed power cannot, however, power your entire house; only the essential items will be powered, such as lights and mobile phone chargers.

The Sonnen battery seems less efficient than the Tesla Powerwall, which has a back-up gateway storing back- up power that can power your entire house needs in case of a blackout. However, a recent update of the back-up box to the SonnenProtect, which is slightly larger providing up to 2.5kW continuous output, seems to be more efficient than the Back-up Box.


Sonnen batteries being premium options also makes them costly for people on tight budgets. With the rise in demand for solar energy storage, it has become more affordable to get one. Costs can be expected to continue declining with an increased production rate. On the same note, you can check for energy storage incentives in your area to offset some of the costs. The cost of a Sonnen battery varies in the capacity of the array you choose to buy and where you buy it. Sonnen batteries face significant competition from other energy storage companies due to their hefty prices. Tesla solar batteries, for example, are way cheaper than Sonnen batteries.

Comparison between Sonnen Solar Batteries and Tesla Power Wall

Tesla has gained quite a reputation in the world of renewable energy with homeowners loving the Tesla home energy storage systems along with electric cars, thereby being the most significant competition to Sonnen batteries. Here are a few distinguishing features between the two reputable cells.


  • Tesla Powerwall has an internal thermal cooling system which is absent in Sonnen batteries.

  • Sonnen uses Lithium Iron Phosphate, which is the safest known chemistry of cells and also more durable as compared to Tesla cells, which are made of lithium NMC.

  • Tesla offers an efficiency of 90% per trip, while Sonnen provides higher efficiency of 98%.

  • Sonnen batteries come in a broader range of sizes from 2.5kWh to 15kWh, while Tesla Powerwall is available in one capacity of 13.5kWh.

  • Tesla has a weather rating of IP56 for outdoor installation with added advice to store it away from direct sunlight, in a sheltered area. In contrast, Sonnen can withstand temperatures of up to 45-degrees Celsius making it more suitable for outdoor installation.

  • The prices of Tesla Powerwall are around $13350 depending on the retailer, while Sonnen's battery price is approximately $14150.

Sonnen Battery Will Appeal to:

  1. Customers who would like a nice looking all in one product for their home energy solar system.

  2. Customers who want to make use of smart tariffs and charge off peaks.

  3. Electric car users who have or are going to get solar panels.

Why Choose Sonnen Battery

It is the leading solar energy storage battery with over 50,000 installations worldwide. Sonnen experts have more than six-year of experience, giving them a competitive edge in quality battery production. Their batteries come at a higher cost than others since they use Sony cells, which are expensive, but the best there is and the safest for residential use. They also have the most extended product warranty of 10 years or 10,000 cycles, whichever comes first. It is more beneficial to go for quality batteries with assured longevity and in the process, saving you more money than you purchased it.

Find a Competent Solar Battery Installer Near Me

At Sun Solar Electric, we offer exceptional services and guide you through your journey to a cleaner, more sustainable energy. We offer our clients services related to solar power installations for residents around the Bay Area and Northern California. If you would like to know more about Sonnen batteries or are looking to explore other energy storage systems, get in touch with us. Contact us at 707-658-2157 for more information.

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