eVault MAX 18.5 kWh | Whole-Home Power, Built to Last

A high-capacity 48V LFP battery designed for whole-home backup, seamless integration, and long-term energy independence — with 18.5 kWh of reliable storage.

eVault MAX 18.5kWh Battery

Built to Last Whole-Home Power

The eVault MAX 18.5 kWh is Fortress Power’s most advanced 48V lithium iron phosphate (LFP) battery, delivering whole-home and light commercial energy storage in a compact, all-in-one design. Scalable up to 370 kWh, it’s ideal for applications ranging from off-grid living and backup power to solar self-consumption and peak demand reduction.

Engineered for simplicity and performance, the eVault MAX features AC and DC coupling options and a serviceable top-access design that makes installation faster and more reliable. Whether you’re powering a home, small business, or critical backup system, the eVault MAX offers the safety, capacity, and flexibility to get the job done.

Applications

Residential

Light Commercial

FEATURES

  • High-Capacity, Scalable Storage

    Delivers 18.5 kWh of energy storage, scalable up to 370 kWh, making it ideal for whole-home backup, large residential projects, and light commercial applications.

  • Long-Lasting Performance

    Engineered for durability with 8,000+ cycles at 80% DoD, the eVault MAX ensures dependable, long-term energy storage and lower lifetime costs.

  • Exceptional Efficiency

    Operates at up to 98% round-trip efficiency at 0.5C, maximizing energy savings and performance across a wide range of usage scenarios.

  • Smart Battery Management System (BMS)

    Equipped with a digital BMS for cell-level monitoring, automatic balancing, and enhanced safety — ensuring consistent, optimized operation.

  • Climate-Controlled Performance

    Engineered for consistent reliability in both hot and cold environments, ensuring optimal battery operation year-round.

  • Certified for Safety & Compliance

    Fully compliant with UL1642, UL1973, and UL9540 safety standards, ensuring peace of mind and simplified permitting and inspection processes.

  • Installer-Friendly Design

    Features top-cover service access for easy installation and maintenance, reducing labor time and minimizing installation errors.

  • Integrated Display & Smart Connectivity

    Includes a built-in LCD touchscreen for real-time performance metrics and supports closed-loop inverter communication for seamless energy management.

PRODUCT INFORMATION

Total Energy (kWh)18.5
Capacity[Ah]360
Nominal Voltage [V]51.2 (48)
Voltage Range[V]48-55
Recommended Charge Current [A]150
Max. Charge Current (Continuous)[A]180
Max. Discharge Current (Continuous)[A]180
Max. Pulse Current (for 10 sec) [A]200
Charging Temperature[F]32 to 120
Discharging Temperature[F]14 to 77
Dimension [H xW x D, inch]20.3 x 20.3 x 42.2
Weight[lbs]520
Enclosure Protection RatingIP55
Mounting optionsFloor standing
CertificatesUL 1642, UL1973, UL9540
Warranty10 Years
ScalabilityMaximum 20 in Parallel (370 kWh)
CommunicationCAN/RS485
High Current Circuit Breaker250A
Efficiency>98%

VIDEO LIBRARY

eVault MAX 18.5kWh Video Library

5 Videos

PRODUCT COMPATIBILITY

Two Apps. One Powerful Energy Ecosystem.

The Fortress Power Owner and Pro apps give homeowners and installers the right tools to monitor, manage, and support Fortress Power systems, anytime, anywhere.