Home Battery Backup Systems
Harness The Grid.
Own Your Power.
UL-9540 certified home battery backup systems that store solar or grid power for outages and everyday energy use. Get dependable whole-home battery backup with scalable storage, engineered and supported in the USA.

Compare Home Battery Backup Systems
Swipe to compareBigBattery ETHOS ESS
- Lowest System Price
- Easiest Installation
- Modular Capacity
- 12-year US warranty
- Reliable Redundancy - Full power from multiple independent modules
- Ultra Thin Low Profile - Save space with sleek design
- Single Person Install - Lighter modules & one person install
The BigBattery ETHOS is our flagship modular home battery backup system, designed for safety, scalability, and cost-effectiveness. Each 5.12kWh LFP module stacks into a plug-and-play rack system, allowing homeowners to tailor battery storage to their energy demands. Built for grid-tied backup with seamless solar integration, ETHOS provides reliable stored power during outages and can scale as your home's energy needs grow.
- Lowest System Price
- Easiest Installation
- Modular Capacity
- 12-year US warranty
- Reliable Redundancy - Full power from multiple independent modules
- Ultra Thin Low Profile - Save space with sleek design
- Single Person Install - Lighter modules & one person install
The BigBattery ETHOS is our flagship modular home battery backup system, designed for safety, scalability, and cost-effectiveness. Each 5.12kWh LFP module stacks into a plug-and-play rack system, allowing homeowners to tailor battery storage to their energy demands. Built for grid-tied backup with seamless solar integration, ETHOS provides reliable stored power during outages and can scale as your home's energy needs grow.
Starting at $5604.99
See ConfigurationsBattery Capacity | 5.12kWh/module
Stack, scale, & save
starting at $252/kWh
Scalable System | 92.1kWh
Expandable for residential
& commercial needs
Warranty | 12-Year
Industry-leading with
USA-based support
Cycle Life | 8,000+ cycles
LiFePO₄ chemistry with
8000+ cycle life
Starting at $5604.99
See ConfigurationsEG4 Wallmount 280Ah All Weather ESS
- Rugged Outdoor
- Fewer Parts
- Flexible Application
- 10-year US warranty
- Field-Serviceable Modules – Quick maintenance without disassembly
- Dual Fire Arrestors – Enhanced outdoor safety protection
- 600A Integrated Busbars – Simplified high-current connections
The EG4 All Weather ESS is engineered to perform in any environment, from hot deserts to cold, damp climates. Offering true all-weather resilience, it integrates seamlessly with EG4’s inverter lineup, including the 12kPV and FlexBOSS series. Built with UL 9540 certification, this ESS ensures code compliance, safety, and reliability for solar installers and homeowners seeking durable, scalable power.
- Rugged Outdoor
- Fewer Parts
- Flexible Application
- 10-year US warranty
- Field-Serviceable Modules – Quick maintenance without disassembly
- Dual Fire Arrestors – Enhanced outdoor safety protection
- 600A Integrated Busbars – Simplified high-current connections
The EG4 All Weather ESS is engineered to perform in any environment, from hot deserts to cold, damp climates. Offering true all-weather resilience, it integrates seamlessly with EG4’s inverter lineup, including the 12kPV and FlexBOSS series. Built with UL 9540 certification, this ESS ensures code compliance, safety, and reliability for solar installers and homeowners seeking durable, scalable power.
Starting at $6489.97
See ConfigurationsBattery Capacity | 14.3kWh/module
Modular battery modules for
easy expansion
Scalable System | 85.8kWh
Expandable for residential
& small commercial needs
Warranty | 10-Year
EG4 manufacturer support
within the USA
Cycle Life | 8,000+ cycles
LiFePO₄ chemistry with
8000+ cycle life
Starting at $6489.97
See ConfigurationsEG4 Wallmount 314Ah All Weather ESS
- High capacity storage
- Connected Ownership
- High-Density Energy
- UL Certified Whole-Home
- EG4 Smart BMS – Active cell balancing for improved efficiency and longevity
- Scalable System Architecture – Auto-Addressing Integration with closed-loop
- IP Rated – Supports to withstand dust, water, and temperature extremes
The EG4 WallMount 314Ah All-Weather Battery is a high-capacity 16kWh, 51.2V LiFePO₄ energy storage solution designed for outdoor solar and whole-home battery backup systems. Featuring a rugged IP67 enclosure, built-in cold-weather heaters, and smart Bluetooth/Wi-Fi monitoring, it delivers dependable performance in demanding environments. When paired with the FLEXBOSS18, it provides a scalable, certified home power battery backup platform for residential energy storage.
- High capacity storage
- Connected Ownership
- High-Density Energy
- UL Certified Whole-Home
- EG4 Smart BMS – Active cell balancing for improved efficiency and longevity
- Scalable System Architecture – Auto-Addressing Integration with closed-loop
- IP Rated – Supports to withstand dust, water, and temperature extremes
The EG4 WallMount 314Ah All-Weather Battery is a high-capacity 16kWh, 51.2V LiFePO₄ energy storage solution designed for outdoor solar and whole-home battery backup systems. Featuring a rugged IP67 enclosure, built-in cold-weather heaters, and smart Bluetooth/Wi-Fi monitoring, it delivers dependable performance in demanding environments. When paired with the FLEXBOSS18, it provides a scalable, certified home power battery backup platform for residential energy storage.
Starting at $7114.97
See ConfigurationsBattery Capacity | 16kWh/module
High-capacity LiFePO₄ storage
per wall-mounted battery
Scalable System | 512kWh
Expandable up to 32 batteries
for residential & commercial
Warranty | 10-Year
EG4 manufacturer support
within the USA
Cycle Life | 10,000+ cycles
LiFePO₄ chemistry tested at 80% depth of discharge
Starting at $7114.97
See ConfigurationsEG4 Wallmount 314Ah Indoor ESS
- High capacity storage
- Auto-ID plug & play
- Built for longevity
- Latest generation BMS
- Quiet, Compact & Efficient – Natural cooling for silent performance
- Heavy Load Support – 200A output for demanding loads
- Dual-Mount Flexibility – Supports both wall and floor installation
The EG4 WallMount 314Ah Indoor Battery delivers 16kWh of dependable energy storage with 200A continuous output—making it a powerful core component of any home or small-business ESS. Fully compatible with the EG4 FlexBoss18 and FlexBoss21 inverters, it forms a scalable, high-performance energy storage system that provides reliable backup, efficient daily cycling, and smart power management. Its compact indoor design, advanced BMS, self-heating feature, and long 10-year warranty make it a trusted solution for long-term, whole-home energy independence.
- High capacity storage
- Auto-ID plug & play
- Built for longevity
- Latest generation BMS
- Quiet, Compact & Efficient – Natural cooling for silent performance
- Heavy Load Support – 200A output for demanding loads
- Dual-Mount Flexibility – Supports both wall and floor installation
The EG4 WallMount 314Ah Indoor Battery delivers 16kWh of dependable energy storage with 200A continuous output—making it a powerful core component of any home or small-business ESS. Fully compatible with the EG4 FlexBoss18 and FlexBoss21 inverters, it forms a scalable, high-performance energy storage system that provides reliable backup, efficient daily cycling, and smart power management. Its compact indoor design, advanced BMS, self-heating feature, and long 10-year warranty make it a trusted solution for long-term, whole-home energy independence.
Starting at $6692.97
See ConfigurationsBattery Capacity | 16kWh/module
Scalable battery modules for
easy expansion
Scalable System | 256kWh
Expandable for residential
& commercial needs
Warranty | 10-Year
EG4 manufacturer support
within the USA
Cycle Life | 10,000+ cycles
LiFePO₄ chemistry with
10,000+ cycle life
Starting at $6692.97
See ConfigurationsHome Battery Backup Built to Save & Back You Up
Stay connected to the grid without depending on it for every moment of power. These UL-certified home battery backup systems store energy for outages and everyday use, with scalable capacity, solar integration and U.S.-based support.
U.S.-Based Support
Live chat, call & email with real energy experts — never offshore.
10–12 Year Warranty
Long battery coverage, backed by U.S. manufacturers that stand behind it.
Fast, Free Shipping
Complete systems ship nationwide in 1–3 business days from CA & TX.
UL-9540 Certified
Code-compliant, permit-ready systems built for safe grid interconnection.
Grid-Tied Customer Reviews
“Excellent upgrade for my Club Car, ditching the old water-filled lead-acid batteries for these lithium packs was a game-changer. Their technical support was solid and walked me through everything I needed to know over the phone.”
“Would recommend the 48v Husky 2 all day long. We use these for a mobile food facility and the Husky 2 battery is an extremely capable battery. Ask for Dylan if you inquire, super helpful. ”
“I had a great experience with Big Battery’s tech support. When I called, Dylan answered right away and immediately began troubleshooting with me. He quickly diagnosed that the charger was the issue and sent out a replacement right away”
All Grid-Tied Home Battery Backup Systems
ETHOS + FlexBoss18 / 10.24 kWh System
Modular grid-tie + backup
EG4 314Ah Indoor + FlexBoss18 / 16 kWh System
High-capacity indoor ESS
EG4 280Ah All-Weather + FlexBoss18 / 14.3 kWh System
Rugged whole-home ESS
ETHOS + EG4 18kPV / 10.24 kWh System
Modular grid-tie + backup
ETHOS + FlexBoss21 / 10.24 kWh System
Modular grid-tie + backup
EG4 280Ah All-Weather + EG4 12kPV / 14.3 kWh System
Rugged whole-home ESS
EG4 280Ah All-Weather + EG4 18kPV / 14.3 kWh System
Rugged whole-home ESS
EG4 280Ah All-Weather + FlexBoss21 / 14.3 kWh System
Rugged whole-home ESS
EG4 314Ah All-Weather + FlexBoss18 / 16 kWh System
Max whole-home capacity
EG4 314Ah All-Weather + FlexBoss21 / 16 kWh System
Max whole-home capacity
EG4 314Ah Indoor + FlexBoss21 / 16 kWh System
High-capacity indoor ESS