Over a month to have a service call and over four months to resolve my battery failure meant that all cells needed replacement. This is just the latest in a series of long outages related to hardware failure or software updates. Initially Sonnen would monitor the system and be aware of problems, but not any more. Sonnen has spun off its warranty… Read more
work to a service company Enervision. It is faceless and impossible to call, and follows a delaying protocol to cut costs. I would strongly recommend against having a sonnen battery installed in Australia.
Reviews with attachments
Bought a house recently with a Sonnen Battery already installed. Simply wanted help to update ownership details and register the App. Since I cannot change the ownership myself and you can only get support via the App no help is possible. Crazy and illogical is an understatement. So for a German company this surprises me even more. It seems… Read more
customer service in Australia is non existent. Also we lost power for just over an hour recently and the battery provided no back up power so completely useless !
AVOID AT ALL COSTS - Run from Sonnen as fast as possible. Sonnen = Worst Customer service we’ve ever had. (Please bear in mind this is a Premium priced product in line with Tesla etc). Sonnen customer service in Australia almost doesn’t exist (run by Enervision Pty Ltd). The major problem with our experience with Sonnen is the deliberate… Read more
manner as a customer if there is an issue, you have to deal with Sonnen directly (Feels like a Cult).
They want you to bypass your installer and deal with them directly. For us this has meant, you are left in the dark (literally) when it comes to the actual problems with your system, how these issues can be fixed and how other companies resolve issues (things the installer you bought the product from could potentially help you with).
Sonnen want you to accept their version of the issue, their interpretation of Consumer Law and what they deem is the best way for them to solve it. Even after all the issues stated below we made it clear we would stay a customer with Sonnen if they replaced our current system as we are having the same issues each year. (Sporadic charging, no back up, modules failing).
Under Australian consumer Law if there are continual issues or more than one issue you are entitled to a replacement. Unfortunately Sonnen customer service don’t acknowledge Consumer Law or more than one issue with our system, just their warranty for replacement reconditioned modules. In the latest failure and after 20 or so emails back and forth and 6 months on, they are still pushing reconditioned modules and no replacement. So we are forced to either get legal advice, go to the media or replace the system.
I have tried to escalate the issue past the customer service manager (who works for Enervision official service provider for Sonnen - not technically Sonnen). He will not let me speak to his manager (or anyone else in the multinational Sonnen group) and his word is final apparently.
The manager did specifically offer some compensation, then back tracked and decided that a battery with 2 weeks offline, constant gradual loss of power for months and no back up facility, didn’t warrant a cent of compensation.
Our Sonnen Battery Issues
(Battery is 4 years old November 2025) - We still have to call customer service when the seasons change or if there was a software update because the change resets the battery settings and pushes energy to the grid sometimes in place of fully charging the battery.
- Sonnen withdrew their support phone number and only deal with customer issues through their app or email, making the process much longer to get anything done.
- After a couple of years the battery stopped fully charging, 2 modules had failed. Took a few months of waiting to get them replaced. (battery was taken offline for a week), no offer of compensation).
When “sonnen installer” came to replace the modules, the replacements were dead on arrival, he had to go away and return with another set of reconditioned modules.
A few months later, the battery started charging sporadically so for the second time Sonnen took the battery offline for a week again, Sonnen couldn’t find a problem. (Turned the battery on, that was roughly 6 months ago) Since taking the battery offline for testing, the battery has slowly been gradually losing power. It only charges up to 68% on full charge, we now have 2/3 of the system we paid for.
Backup power doesn’t function, when battery doesn’t charge properly
- Sonnens solution is to offer a 4th set of modules to replace the replacements to the replacements…. (no thanks).
Additional Issues We were part of their initial Virtual Power Plant, that was scrapped. It’s difficult to join other VPP’s or Amber as the Sonnen battery isn’t supported
- Sonnen original mobile phone app would always crash on my iphone, when trying to change the backup power (that is now replaced). Contacted customer service, no reply. Happy to say the old app has been replaced a while back and it now works (at least something does).
The photos attached are our Battery and the disconnected DODGY modules being taken away whilst the Sonnen Battery was being removed and replaced with a Tesla Powerwall 3.
Please stay away from Sonnen they seem fine until you have a few issues and then you realise like other reviewers here, you’ve bought into a system which wont help or support the product you thought you were buying.
Save time and money go somewhere else.
It's been 11 weeks since we had a 10kWh Evo system installed and we're very happy. From quotations to install + commissioning, we had great service from Tindo and their Electrician, Luke. A challenging job given our switchboard (1984) and unusual battery location but great work done. Sonnen online setup & connection went smoothly and enjoy the… Read more
app. The local management/data access for my home automation system (via a custom integration) was important and works well.
I've had the Sonnen Evo battery installed since late October 2024. Since December, the battery will stop working with a solid red light almost on a daily basis but will then recover itself later in the day. As the installer was unable to resolve the issue, the issue was raised with Sonnen. In the last 3 months, I have tried contacting Sonnen. … Read more
Calling their support number goes to a recorded message to send them a support email. After sending the email with repeated follow ups as I only had one response stating they are busy and will look into it, I finally received another email in March 2025 with a response that Sonnen has checked my system remotely and everything is fine. The failure was probably a software update. I don't think that's the case if the battery fails almost on a daily basis. The battery is not cheap but Sonnen doesn't seem to stand by their products nor provide reasonable support. Thus the one star review. I'm sure I'll give it 5 stars if I didn't had any issues and didn't have to reach out to Sonnen support but that's not the case.
Disappointed after 3 breakdowns – As an update to the earlier review below I feel that it is necessary to now add that the fault was eventually rectified earlier this year by Sonnen and all is working well now (hopefully I am not jinxing myself) It was a shame that the most recent breakdown occurred in the sunny parts of the end of 2024 & start of 2025. 3/9/25 Probably the biggest… Read more
problem with this battery storage system is that you cannot adjust the charge/discharge cycle, this would be beneficial in the Winter months especially. With Sonnen not providing a plan like they did in the past (Sonnen Flat) I think they called it a VPP? Virtual power plant?? —-it now has lost its shine/incentive for purchasing above other systems out there. The only other ‘carrot’ was the fact that the battery cycling was not confined to one per day, I am sure other battery systems offer more efficient options if not the same as this these days……do your homework
I installed a 10kw Sonnen battery when I got panels installed on my roof in 2017. The system failed once in the first few years but was fixed relatively quickly (within 1 month). The system continued to work fairly well until failing again about a further year on. The repair took a little longer this time as a particular part was needed. Part of the viability of the system was being part of a ‘Sonnen Flat’ plan, sadly this is no longer supported/available through Sonnen. The system was upgraded to 16kw battery and additional panels installed as well prior to notification from Sonnen that they were not going to continue the Sonnen Flat plans. The system has stopped working again, no internet connection since September 2024. The internet problem is 100% not from my end (brand new Ethernet cable bypassing house hard-wired cable/new router/wireless router-extender) The circle/eclipse light is not on. I have reset it the correct way, the light stays solid blue/white then the battery cabinet circuit breaker trips off after about 10 minutes………..Sonnen keeps sending me emails saying ‘your battery cannot be monitored/warranted as you are not connected to the internet’ SSOOO Frustrating, just come and fix it already!!! Conveniently, the phone number they provided on their email to me is ‘not connected’
Latest follow-ups
Just over 6wks to rectify a fault identified on day of installation of the system is not a great way to be introduced to Sonnen Customer Service. Poor communication filled with false promises and eventually I had to hound them for action. Not Good Enough. Show details
Follow-up · After pushing Sonnen they agreed to replace a part, I shouldn't have had to push to get a fault fixed
Positive reviews
Inverter on battery playing up , contacted Sonnen through App and had a response within a day ..Follow up and feedback was excellent .I was kept in the loop and notified at every step .. In no a matter of weeks I was up and running again Show details
Very happy with our battery and app. At the 3 year mark it did fail us but using the app to contact Sonnen to resolve the issue, it was within 2 weeks. Can’t fault their communication and timeline process when I explicitly asked for this outline. Show details
We got there in the end! – Sonnen managed to combine the readings for 2 batteries which had not been encountered before but they persisted with their German counterparts and Tindo to finally resolve the issue. Thank you. Show details · 1
Negative reviews
I am incredibly disappointed with both the quality of my Sonnen battery and the complete lack of customer service I have received. My battery began experiencing issues in July, after which I stopped producing and selling solar energy back to the grid. I contacted Sonnen multiple times—via email and through the app—and heard nothing for MONTHS.… Read more
During this time, my electricity bills doubled. Not only were my emails ignored, but when I did finally receive a response, I was told that Sonnen was "busy" and would follow up.
An external test eventually identified a faulty module. I was advised that Sonnen would order the part and arrange a repair. When the electrician finally attended, he replaced the faulty module but informed me that another module was swollen and likely to fail soon. Despite this clear safety and performance concern, Sonnen refuses to replace it until it actually fails. This is completely absurd and unacceptable for a product that costs thousands of dollars.
The lack of communication, the delays, the dismissive responses, and the refusal to proactively address known issues demonstrate an alarming lack of care for customers. To make matters worse, there is no phone number to call for support, leaving customers entirely powerless when problems occur.
I have been without the system I paid for, my electricity costs have significantly increased as a result, and I have had to spend months chasing a response. Frankly, I should be invoicing Sonnen for my electricity bills.
This experience has been incredibly disappointing and has completely eroded my confidence in both the product and the company.
Had a Sonnen Eco battery system fitted in March 2019 and for the most part the system has been faultless. In December 2023 I had my first issue with a failed module. Although the module was replaced under warranty, it took 10 weeks for the repair to be completed. I am now having another issue which started in August 2025, again I emailed support… Read more
and it has now been 4 weeks and still no idea when my issue will be rectified. Support is basically non-existent, if you don't continually email them, they won't give you any updates. For the money this brand costs, you would think they would have a better support service. Sadly this is not the case. I have given them 2 stars but I would rate the product as 4 stars but the support as 1 star. I am located in Australia.
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The customer service for my Sonnen battery is extremely poor. I used to be able to phone them but it appears this form of communication is not offered anymore by Sonnen. I contacted them via the app which took days for a response & the process for repair was to take up to 2 weeks & was asked to shut down the battery until the repair was concluded.… Read more
A few days later I was emailed again by Sonnen to notify me "We have noticed your sonnenBatterie ***** is offline as part of our monitoring process." My question is if they are monitoring the battery why didnt they detect the issue with the battery before I did. This would have meant my battery would have been repaired much earlier
Recent reviews
The team took 3 months to replace the faulty home battery modules. Communication from the team periodically to say the issue was still investigation but lack transparency and reassurance to customers The technician wasn't friendly.
We upgraded a 7yo rooftop solar system with a 10KW Sonnen EVO battery from Tindo Solar in 2023. The system has been quietly running well and significantly reduced our power bill and occasionally powered the house during grid outages, but in late December 2025 the battery developed a fault were it could not recharge (permanent off-grid status). A… Read more
service request was placed via the Sonnen App, but the Christmas shutdown meant that no service technician was available !! The battery was turned off to prevent total discharge, but the solar panels still worked and powered that house and provided grid feed-in during the day. Sonnen service agent (Enervision) was able to diagnose the fault remotely after we turned the battery back on in January, and the technician was able to replace the faulty parts under warranty in mid-February. Although it took a long time to determine the nature of the fault and provide the parts, once the service guy was on site, it was fixed under warranty in half a day.
Battery failed after only 2 days, it's been 3 weeks now waiting for it to be fixed, In the meantime it is costing us money to run our air conditioning after sun down. Very poor customer service, can't speak to anyone, had one email saying about waiting on parts, can only send emails that don't get answered grr Show details
Great hardware - lousy company – The EVO battery hardware is reliable and works well. It's not the cheapest, but good quality can't be compared with the cheap Chinese competitors. I believe it is good value for the excellent hardware quality. Sonnen as an organisation could not be more aloof and disengaged from their customers. Information regarding operation of the battery in… Read more
its backup battery roles is non-existent. In the mobile app the backup reserve amount can be set and there is no other information about this feature anywhere. There are no alerts from the app to let you know the Grid is offline when the backup feature kicks in.
There was a reasonable API used to make home automations to compensate for the terrible mobile app. V1 of the API has security issues. V2 of the API does not provide the same information as V1 and can't be used in its place. The V2 API is incomplete and scant documentation is a beta draft, incomplete with many errors. These issues have been in evidence for some years with no sign Sonnen cares about its customers' needs at all.
Poor service department – Do yourself a favour and do not get this product. When it works it is fine but the after care from the service department is abismal. So far this time it has been a week since we reported that there was a fault and that the battery is not charging. You cannot contact them by phone and they do not respond to messages left on their app. We have had… Read more
two generic replies that do nothing to resolve the issue , have received one phone call stating we need a technician to come out and surprise surprise no call or contact from the technician. Last time we had an issue they at least had a phone line to contact but even then it took 3 weeks to resolve and multiple phone calls. The reason for having the battery was to reduce /stop using the grid. Will we be compensated for this issue - I doubt it.
Warning don't buy a sonnen battery – Don't buy a sonnen evo battery the internal fan runs continuously at a very very noisy level. Sonnen claim this is necessary to cool the components. The cabinet has a minuscule vent at the back so very little air is drawn into the cabinet, in reality all the supposed cooling fan does is circulate hot air. DON'T BUY A SONNEN BATTERY AS THE NOISE FROM THE FAN WILL ANNOY YOU AND YOUR NEIGHBOURS. Show details
A great product ruined by non-existent support – The battery itself is good, when it works. However, the support is non-existent. When I bought the battery, they had a phone support line and fast responses via the app. They also had a VPP. All that is now gone. They don't respond to messages on the App or to emails. I now have a $10000 bollard sitting in my garage, doing SFA, due to the totally inept team at Sonnen. Show details
Buy a different brand – Even the Sonnen CEO’S AI on X will tell u their customer service is crap. Customers can wait weeks, months. U can receive generic response or can be directed to self reboot the system without further assistance, even after diagnosing issues that require professional intervention. My battery is 5yrs old I can’t buy any more batteries for it. Their Elizabeth address is nothing more then a P.O. Box, there is no phone number
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Regretting the purchase – Broken twice within 14 months from installation. The second time Sonnen has not responded, I have been waiting for 6 days by now. I have no idea when they will repair the battery, nobody calls me and no phone number to call - except for the installer who said they passed it on to Sonnen and allegedly don't know anything. In some reviews… Read more
people said they waited 6 months for their issue to be fixed - I hope this won't happen to me, but I am worried. The app was freezing for more than 6 months, now working. I would think twice about buying Sonnen if I knew what I know now.
My battery was out of order from mid December 2024 till mid January 2025. They emailed me just… Read more (+1 reply)
Internal fan running 24/7 – Customer service is appalling, from the installers "first was phone calls to the installers that went unanswered, then to emails" then they contacted Sonnen, the installers sat on my case for one month before passing it on to Sonnen which was nearly another month, then had to wait for Sonnen to get back to me with the empty promises of a tech in… Read more
your area will soon be in touch in the next few days. Nothing. Sent an email back, and they are now silent about the internal fan running 24/7 and what will be done there? Battery good, warranty service needs overhauling.
Update, finally fixed after waiting three months! And it was not the Sonnen tech who was supposed… Read more
Battery works as advertised but Sonnen support is non-existent – The battery (installed 2018, 7.5 kW) works as advertised but the discontinued SonnenFlat scheme ended more like a rip-off than an energy revolution. User have been left with an unmanageable battery and no support. What is most peeving is the absolute lack of human support on the advertised Sonnen Australia support number, which is a recorded list… Read more
of email support addresses and no option to speak to a human. The Sonnen web portal is likewise marginal and often fails to supply data. Please Sonnen, give your Australian customers some more human support for the many dollars they have paid you.
No battery control after sonnen unplugged their VPP – I have had a 10kWh Sonnen Battery with 6.6kWh of panels for 3 years. I got the sonnenFlat power plan free for the 1st 24 months (normally $49/mth) and this VPP plan was good value and good use of the battery. sonnenFlat themselves were very poor at issuing bils / statements, with several periods when nothing was issued for 4-5 months. Seems like… Read more
they ended up deciding it was too hard and so have pulled the plug on the sonnenFlat VPP. The issue now is that I can't get the full benefit of the battery. Yes in summer it will charge the battery during the day and use at night. However I can not force it too charge during the day (10am-3pm when power is cheapest) in winter on days when there is little/no solar. This is because Sonnen have not provided any battery control options where I can chose when to charge or discharge. I have tried to contact them about this and can not get any response. This also means I can not take full advantage of any providers that allow you to pay wholesale rates. There are several providers that run their own VPP or have options for battery control (like Amber), but none of them work with a sonnen battery. So basically I now have what is probably the dumbest battery (more acurately the software, in not having any control) you can buy. So as it stands now I would not recommend a Sonnen battery as it is now even to harder to make it pay for itself, even though technically I can not fault it.
Terrible after sale service – Terrible after sales service. Bought for $11,000 3 years ago and now not working. What is even worse is that I have 2 solar systems and all that power is now going to waste as the battery has been offline for over a month. No human to talk to, did receive one email saying Sonnen is waiting for parts but absolutely no idea of how long it would be. Cannot see how they know what part is needed as they have never come out to check it. Hopeless! Show details
Fixed last week after 2 months offline. All good now.
Sonnen leaves customers with 'dumb, rudderless' Battery after ripping away their signature plan – We purchased a SonnenBatterie Hybrid 9.53 three and a half years ago. Despite the high price, we were convinced by the promise of the SonnenFlat plan, which would provide year-round value for money, even with our home’s mediocre solar generation potential. Fast forward three years, and Sonnen is discontinuing the SonnenFlat plan, even though they… Read more
still advertise it as a key benefit of owning a Sonnen battery.
Our solar yield during the winter months is negligible, and without the SonnenFlat plan, we now have to purchase nearly all our winter electricity from the grid, on top of paying off the over $13,000 investment in the battery.
Frustratingly, unlike most batteries, the Sonnen system doesn't offer open API software to allow third parties to manage the battery’s charge/discharge cycles. Sonnen has decided not to grant its customers access to this feature, which could have saved us thousands.
Now, without the SonnenFlat plan, our battery is essentially useless. It fails to maintain a state of charge during peak periods and often makes poor decisions, such as charging itself with 100% grid power during peak electricity price periods.
Financially, we are significantly impacted. Sonnen should have opened their battery API before discontinuing the SonnenFlat plan, leaving their customers without support. This change came without warning, leaving us with nothing but an awkwardly worded email. It’s unfair and should not have happened this way.
Up and down the ladder to restart battery – Installed the battery about 3 years ago. The system is cutting off. During first 6 months I received weekly phone calls asking me to restart the battery. The restart button is on the top of the battery so I keep a small ladder next to the battery. After about 6 months, I refused to climb the ladder to restart the battery. I am 65 years of age and… Read more
have knee problems. I was told that I had a Black Out Protection. After a power cut in the area I realised that the Black Out Protection is not working. I rang Customer Service, they insist that their system shows Black Out Protection is installed and should be working. I have no light during black out and gave up calling Sonnen about this issue. Since December 2023 the battery is constantly showing red light so I called Sonnen. They kept asking me to restart the battery avery few days again. In February 2024 I was told by Sonnen that the battery is off line since December 2023 and most likely the inverter needs to be replaced. Sonnen said they do not have spare inverters in Australia and do not know when they will have some. As of 28 April 2024 i do not know when the battery will be fixed. I have now lost the entire somer and received a bill of over $4,000 for electricity. I assume the battery never worked properly because I am a single person household and the electricity usage is an estimate.
After I wrote the review, the next day I received a phone call from Sonnen advising that my case… Read more
Modular battery systems are NOT really expandable – I own a sonnenbatterie 8.2, which was installed mid 2021. This included a large battery cabinet, supposedly modular, which was designed to be able to expand the system. Within 1.5 years of installation the manufacturer discontinued the battery modules. There is now no means of expanding the system and I have a half empty huge cabinet in my… Read more
garage. Sonnen are unable / refuse to assist with procurement of additional modules.
Beware that any batteries purchased from sonnen are not modular / expandable, even if advertised as such!
A pity, given otherwise the after service / phone support is great.
Hi Ed, thank you for your feedback. Please note… Read more (+1 reply)
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Update - it took 3 months to resolve the problem. No compensation, no apology and it was only after… Read more