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The BigBattery ETHOS Expansion Kit adds a second stack of ETHOS battery modules to an existing ETHOS system. Choose the 2x kit to add two 5.12kWh modules (10.24kWh), or the 3x kit to add three (15.36kWh). Each kit comes with the rack base and the stack-to-stack power and communication cables needed to connect the new stack to your first one.
Because ETHOS is modular, you do not need to replace your batteries or your control box to get more runtime. The new modules join the existing stack in parallel, report to the same ETHOS Control Box and are covered by the same 12-year warranty and lifetime USA-based support.
The 2x kit adds 10.24kWh (200Ah) and the 3x kit adds 15.36kWh (300Ah) of LiFePO4 storage at 51.2V nominal.
A rack base, stack-to-stack power cables and a stack-to-stack comm cable come with the kit, so the new stack sits beside your existing one and plugs into it.
Up to 16 ETHOS modules can run on one control box, more than 80kWh, so most systems can grow without adding a second controller.
Like the rest of the ETHOS line, each module is IP65 and NEMA 4X rated and certified to UL9540A, UL1973 and UN38.3.
BigBattery rates ETHOS modules for 6,000+ cycles, and each has a smart BMS with automatic cell balancing and internal fire suppression.
Longer outage coverage. Double your runtime for essential circuits during multi-day outages.
Adding air conditioning or electric heat. Grow from a starter system to the four to six modules BigBattery recommends for whole-house backup.
More solar storage. Store more of a growing solar array for evening and overnight use.
Versus buying single modules. Single ETHOS modules stack on your existing rack. The expansion kit is the simpler choice when you are starting a second stack, because it includes the rack base and stack-to-stack cables.
Versus a second battery system. A second, separate battery system needs its own controller and wiring. The expansion kit keeps everything on one ETHOS Control Box.
This may be a good fit if
No. The kit connects to the ETHOS Control Box in your existing system.
The 2x kit adds 10.24kWh and the 3x kit adds 15.36kWh.
Up to 16 modules on one control box.
Yes. ETHOS modules carry BigBattery's 12-year warranty with lifetime USA-based support.
The BigBattery ETHOS Expansion Kit adds 10.24kWh or 15.36kWh to your ETHOS system with everything needed to connect the new stack. At Outbound Power, we help customers choose the right parts for their solar and battery systems. If you have questions, our team is happy to help.
BigBattery ETHOS Expansion Kit Specifications |
|
|---|---|
| Kit SKUs | K0698 (2x), K0699 (3x) |
| GTIN-12 (UPC) | 850061252173 |
| Added Capacity | 10.24kWh (2x) or 15.36kWh (3x) |
| Added Ah | 200Ah (2x) or 300Ah (3x) |
| Module Capacity | 5.12kWh, 100Ah each |
| Nominal Voltage | 51.2V (48V system) |
| Chemistry | LiFePO4 |
| Charging Voltage Range | 55.6V to 57V |
| Operating Voltage Range | 48V to 57V |
| Max Charge Current | 200A |
| Charge Temperature Range | 32°F to 113°F |
| Discharge Temperature Range | -4°F to 140°F |
| Module Dimensions (D x W x H) | 6.7 x 26.5 x 16.14 in |
| Module Weight | 121 lbs |
| Max Connections | Up to 16 modules per control box |
| Communications | CANBus, RS485 |
| Protection Rating | IP65 / NEMA 4X |
| Certifications | UL9540A, UL1973, UN38.3 |
| Warranty | 12 years |
Yes! Outbound Power is an Authorized Dealer for every single brand and product on our store.
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