Marcus R.
2025-10-15
Exceeded expectations
The StackMax Flow 220 has been running flawlessly. Sizing was spot-on and install was clean.
Verified purchase
Why we recommend this
Our Energy Score for this model is 58/100 (Fair). We weighed round-trip efficiency, warranty depth, compatibility, and real-world use cases for inverters & hybrid.
- LiFePO4 chemistry with long cycle life
- Integrated BMS with thermal protection
- Expandable with additional modules
Purchases through our links support independent testing at no extra cost to you.
Overview
StackMax Flow 220 delivers 8 kW of reliable energy storage with LFP Rack cells, intelligent BMS protection, and seamless integration into modern solar ecosystems. Engineered by StackMax for homeowners who demand performance, transparency, and long-term value.
- Whole-home backup
- Peak shaving & demand charges
Compatibility
HomeCommercial
Pros & cons
Pros
- LiFePO4 chemistry with long cycle life
- Integrated BMS with thermal protection
- Expandable with additional modules
Cons
- Requires compatible inverter for full backup
- Professional install recommended
Technical specifications
- Capacity
- 8 kW
- Voltage
- 240 V
- Chemistry
- LFP Rack
- Warranty
- 10 years
- Cycle Life
- 6000 cycles @ 80% DoD
- Operating Temp
- -4°F to 122°F (-20°C to 50°C)
- Max PV Input
- 10 kW
- Switchover
- < 10 ms
- Efficiency
- 97.4%
Compare similar models
Customer reviews
Priya N.
2025-09-15
Solid performance
The StackMax Flow 220 has been running flawlessly. Monitoring is intuitive and savings are real.
Verified purchase
Tom V.
2025-08-15
Great value
The StackMax Flow 220 has been running flawlessly. Monitoring is intuitive and savings are real.
Verified purchase
Dana W.
2025-07-15
Great value
The StackMax Flow 220 has been running flawlessly. Monitoring is intuitive and savings are real.
Verified purchase
Elena K.
2025-06-15
Great value
The StackMax Flow 220 has been running flawlessly. Monitoring is intuitive and savings are real.
Verified purchase
FAQ
Most residential battery and solar equipment qualifies for the 30% federal ITC when paired with solar. Consult your tax advisor for your specific situation.
Affiliate disclosure: We may earn a commission if you buy through our links. Price and availability are set by the retailer and may change. Always confirm the current price before checkout.
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Price shown is for comparison only. See the live price at checkout.
$2,575
4.7
- Capacity
- 8 kW
- Voltage
- 240 V
- Cycles
- 4,000
- Weight
- 76 lbs
Affiliate disclosure: We may earn a commission if you buy through our links. Price and availability are set by the retailer and may change. Always confirm the current price before checkout.