GROWATT 3686Wh Extra Battery for HELIOS 3600 Portable Power Station, LiFePo4 Expansion Battery, 9 DC Outlets for Cell Phone, PC, Tablets or Other Devices, for Home Use, Emergency, Camping and RV
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Arrives
Monday, Aug 31
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Set name: HELIOS 3600 Extra Battery
Features
- Dual Function Design for Flexible UseThis 3600Wh expansion battery pack comes with various output ports on the unit itself. It can be stacked with main power station to expand total power capacity, and it is also available for independent power output alone. Dual-purpose design brings great cost-effectiveness and saves your extra purchase cost.
- Charge via Main Unit ConnectionThis auxiliary battery needs to be charged by connecting with the main power station through dedicated cable. It realizes convenient power replenishment through the main unit, forming a complete matching power supply system.
- Large Capacity Effectively Extend Working TimeSingle pack provides large capacity, multiple packs can be connected in stack to greatly extend the working duration of main unit, well suited for long time emergency power supply and off-grid power use.
- Independent Output for Multi-scene ApplicationAfter fully charged, you can separate it from the main unit directly. It supports independent power supply outdoors, at home or during travel, easy to carry and widely applicable.
- Long-Lasting, Safe Power & Trusted ServiceEquipped with EV-grade LFP cells, advanced BMS technology, and smart algorithms, it retains 80% capacity after 4000 cycles, ensuring 10 years of stable use. Backed by Growatts global leading reputation in residential solar and inverter industry, you get proven quality, US-based responsive service, and UL certification for peace of mind.
Description
Life doesn’t pause when the power goes out — and with HELIOS 3600, neither do you. Whether it’s keeping the lights on, your fridge running, or your family connected, Growatt’s all-in-one home energy storage system gives you peace of mind every day. With up to 36kWh expandable capacity and instant backup switching, HELIOS 3600 ensures your home stays bright and comfortable, even in unexpected outages. The world’s No.1 residential inverter brand and a top-four global leader in PV and storage hybrid inverters. With 14+ years of expertise, Growatt provides reliable solutions spanning power generation, consumption, and energy management for homes and businesses worldwide. Millions of homes and businesses across the globe trust Growatt’s versatile solutions to power their daily life. With installations in 180+ countries and 6M+ users connected to our cloud platform, Growatt is truly a global leader in energy solutions. 240V Solar Generator Outdoor Solar Kit 10000W Hybrid Inverter 3500W Off-grid Inverter 20kWh Home Battery 10kWh Home Power System 20kWh Home Power System
Brand: GROWATT
Wattage: 3600 watts
Fuel Type: Solar, Battery
Power Source: Battery Powered, Solar Powered
Recommended Uses For Product: 3686Wh Expansion Battery for GROWATT HELIOS 3600 Portable Power Station
Item Weight: 45 pounds
Voltage: 120 volts
Output Wattage: 3600
Special Feature: LifePo4 Battery
Included Components: 5-year Service Card, Battery Expansion Cable, GROWATT HELIOS 3600 Expansion Battery, User Manual
Wattage: 3600 watts
Fuel Type: Solar, Battery
Power Source: Battery Powered, Solar Powered
Recommended Uses For Product: 3686Wh Expansion Battery for GROWATT HELIOS 3600 Portable Power Station
Voltage: 120 volts
Output Wattage: 3600
Additional Features: LifePo4 Battery
Engine Type: 4 Stroke
Total Power Outlets: 9
Starting Wattage: 3600 watts
Frequency: 60 hertz
Runtime: 10 minutes
Item Weight: 45 pounds
Item Dimensions L x W x H: 20.4"L x 12.3"W x 16.5"H
Brand Name: GROWATT
Included Components: 5-year Service Card, Battery Expansion Cable, GROWATT HELIOS 3600 Expansion Battery, User Manual
Model Name: HELIOS 3600 EXPANSION
Model Number: HELIOS 3600 EXPANSION
Number of Items: 1
Manufacturer: GROWATT
Item Type Name: Portable Power Station Expansion Battery
Manufacturer Part Number: HELIOS 3600 EXPANSION
Warranty Description: 5 Year Warranty
Color: black
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Monday, Aug 31
This item is non-returnable:
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
Non-returnable. Transportation of this item is subject to hazardous materials regulation
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Set name: HELIOS 3600*2+Hub
After a few initial hiccups (the Helios units were likely damaged during shipping), Growatt replaced them rather quickly. Overall working to get these replacements wasn’t too difficult. I use my setup regularly to top off the family’s PHEV. We purchased 2 sets of main and backup batteries. The PHEV has a 13kwh battery. Using the Helios 3600 with our 10kwh Growatt whole home solar setup, we charge both these and home batteries. When we get off work, the sun tends to be down, so we can now charge the car without connecting to the grid (or inefficiently pulling from our 25kwh home backup batteries). Product: Pros: 1, A different set of outlets for pretty much any use. 2, Pushes and pulls enough power to charge fast enough that we can unplug the PHEV before bed time (3.5 hrs). 3. App provides a few option and data output that I find useful. 4. Growatt has steadfast honored their warranty. Send them a pic, short video, detailed statement and after a few verification questions, replacement is sent. 5. No Wi-Fi or Bluetooth needed for basic functionality. Cons: 1, These things are heavy (100lbs) and shipping can be rough on them. They are packed as good as possible. 2, EPS is either on or off you cannot choose which. If plugged in and 120v is running EPS is on also. Can only stop it if unplug unit (or use a timer). No app option 3, If using the combiner device to get full 240v, EPS turns off automatically. I get the purpose, but would be nice to have a choice. Overall I say five stars. Delivery seems to be the weak point, but I am not faulting Growatt for that. I would have, but because they do honor the warranty (even if it means having to ship back multiple units) I say five star service. Would I buy again, yes but I always reserve the right to update this review.
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Reviewed in the United States on May 19, 2026 by avahzd
Set name: HELIOS 3600
--- Pros --- Compact size for the amount of power. Fast charging. Solid build. Easy to use app. --- Cons --- Slight humming noise during charging, especially on 1200W+. --- Thoughts --- Quite a powerful battery. Used it to charge two laptops, e-bike, e-scooter, and battery pack all at the same time. Battery was shipped with 50%, used 18% in 4 hours (at the output rate of 20W to max of 311W) the above mentioned devices. Charging the battery back to 50% from 32% took less than 2 hours on 1800W charging through standard outlet. The buttons to enable/disable different outlets was more useful than thought. It also saves power by not having to keep all the converters inside enabled and running. The battery is heavy, but the build is sturdy and feels high quality. The wheels work fine on bumpy sidewalks. The display is useful in checking battery level, output power, and charging rate. The app (MyGro APP) is pretty easy to use. The dashboard page packs a lot of info about the current status of the battery, and just like with the actual battery, allows users to pick what type of outlets are enabled. Having the manual inside the app is also very useful, it saves time having to look up online for the model and make of the current battery. Only complaints for the app is text do not have enough contrast and some English translations being a bit too long for the space provided. Would like to see a revision with the handle moved to the opposite side of the wheels; that way people can pick it up with the handle even if it's turned over when lugging it. Also would like to see some changes to the Wifi/Bluetooth button; it is too easy to accidentally hit the button and turn off the connection. Perhaps making it a "hold to toggle" like with the power button would help? In that case, the enable/disable outlet buttons could also benefit from this feature. Overall, this is a well-built battery that can be used during power emergencies and outdoor use without hassle, along with its companion app that makes it easy to manage and monitor.
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Reviewed in the United States on January 29, 2025 by irobonxt
Set name: HELIOS 3600
I purchased my unit in February of 2025 - it was an excellent resource to power my mobile business for the day and top off overnight in between daily service calls. The unit suddenly stopped accepting a charge from the wall power input. I reached out to customer support and they had me verify the issue via a short video and they sent a replacement unit extremely fast. Customer support is top notch. Couldn't be happier with the unit or their support. Would recommend to anyone looking for a portable power station that works within the specs of this machine.
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Reviewed in the United States on August 13, 2026 by Rick E.
So far these batteries are working out excellent. I can run a portable 8k BTU A/C for about 5 hours on one battery and one backup. Recharge time will vary. Cannot get the Bluetooth or Wi-Fi to work yet. When shipping, I ordered the main battery and the backup, they only tracked one box. So they showed up weeks apart with no clue when the second box would get there. 2nd issue is the operating guide is a little light on subject matter, especially on how to charge it and what all can charge it. They give some details but requires an internet search, and DO NOT USE the Anderson plug without a charge controller….. Overall I am definitely going to buy more, but my expectations and wallet have gotten lower.
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Reviewed in the United States on May 16, 2025 by Robbie R.
Set name: HELIOS 3600+2*200W
After pulling the trigger on something I have wanted and needed for a while, I'm glad to have received a product that finally works as expected with charging times and output levels. I was uncertain about the large battery size & cost, but having used it arund the house and outdoors, I definitely needed the extra capacity! The Growatt 3600 is a good looking and well crafted product that comes in at a great price compared to similar size and spec competitors. I had heard of Growatt in the solar space before and they are seemingly delivering a similar price/value ratio on these smaller units too. I actually do already have access to a gas generator, but the gas refueling is time consuming, so I decided to try a large electric generator that can actually last all day for offgrid electronic and tool use. I also like that it charges at the max possible rate of a wall outlet at 1800W. The growatt Mygro app for the device is great fr monitoring and easy to connect to adjust charging speed which is necessary for me when offgrid, but the 2000W solar input is great, not sure I will ever max it out, but may get some additional panels. Also nice to know I can parallel another device to get 240V output if needed in the future. Overall a great device & would highly recommend.
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Reviewed in the United States on December 18, 2024 by Dmitriy Filonov
Set name: HELIOS 3600
Day 1 of connecting it, I fully charged it with my solar panels, when I tried connecting to the ac, the button came on for less than a second, then immediately popped right back off again. The light showed green on the button and the icons displayed on the screen. I was able to connect to it through the app via bluetooth but it would not connect to wifi, the firmware is up to date. When I called customer support, I got disconnected the first time, talked to someone the second time that was literally ready to warranty it out as soon as I mentioned the problem. When I got upset about it being a bad product that they shouldn't be selling in the first place and the inconvenience it is to me, he started going through the troubleshooting, all of which is mentioned above, and that's literally the only thing he offered. When I requested to speak to a manager about the invonvenience of it all, he said the managers are in China, and they only respond via email. Don't waste your time or money, I was thinking about purchasing an expansion battery, so glad I didn't.
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Reviewed in the United States on March 16, 2026 by Amy C.
Set name: HELIOS 3600
Very impressive and high quality portable power station Works great in our cabin. Run air-conditioning, fridge and other appliances directly from the power station without any issues I charge with solar panels and also anderson cable plugged into the vehicle while running It's pretty heavy and a little difficult to turn but the long handle is very convenient to move to around Did have some issues with app not updating the firmware. I contacted the after sales team and they help resolve the issue very quickly The device supports 12 to 60v solar PV with h max 2000W 800watt anderson input
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Reviewed in the United States on July 2, 2026 by Thomas
Set name: HELIOS 3600+2*200W
I very rarely write reviews. 5 star (so far) on equipment. 0 stars on app. The permissions required are nothing short of predatory. Shame on you Growatt. Will be selling off and changing brands asap. Without the app functionality is significantly lessened.
Reviewed in the United States on January 24, 2026 by Dustin C