• A rectangular silver and black lithium iron phosphate battery, labeled Fortress Power eFlex 5.4kWh, with ribbed sides and connectors on one end, offers reliable energy storage by Fortress Power against a white background.
  • The Fortress Power unit is a rectangular, black and gray energy storage solution with a central digital display, indicator lights on the front, ribbed sides, and a robust industrial design.
  • A black and silver rectangular Fortress Power eFlex 5.4kWh lithium iron phosphate battery features front ports, a switch, LED indicators, and labeled terminals for easy energy storage identification.
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Fortress Power eFlex 5.4kWh 48V LFP Battery

SKU: eFlex54G2
Availability: In stock
$1,789.00
$2,199.00 $1,789.00
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Compact LFP Battery · 48V · 5.4kWh

Fortress Power eFlex 5.4kWh 48V LFP Battery

Discover the Fortress Power eFlex 5.4kWh LFP Battery, the versatile and efficient energy storage solution tailored for your home or business needs. This lithium iron phosphate battery pack, with its compact 5.4kWh capacity, ensures dependable power backup for shorter durations, ideal for those seeking a smaller yet powerful energy storage option.

5.4 kWhTotal Energy
6,000Life Cycles @ 80% DoD
7yrWarranty
>98%Round Trip Efficiency
Features

Features

  • Compact 5.4kWh battery pack: Perfect for limited spaces and efficient energy storage.
  • Lithium iron phosphate (LFP) technology: Delivers long-lasting and reliable performance.
  • Advanced battery management system: Ensures optimal performance and safety.
  • Ease of installation and maintenance: User-friendly design for hassle-free setup and upkeep.
  • Wide compatibility: Works seamlessly with various solar inverters and charge controllers.
  • Durable design: Built to endure harsh environments and extreme temperatures.
  • Safety certified: Meets UL9540 and UN38.3 standards.
  • 7-year warranty: Offers peace of mind with long-term coverage.

The Fortress Power eFlex 5.4kWh LFP Battery provides robust and sustainable energy storage, ensuring your energy needs are met even during outages. It is an excellent addition to any solar panel system, offering reliability and efficiency for years to come. This battery pack is a top choice for those with limited space, seeking a compact and dependable energy storage solution.

The Fortress Power eFlex 5.4 kWh works seamlessly as a compact unit on its own, but it can also be integrated into larger systems.

You can also browse the full collection of house backup batteries to explore additional lithium storage options tailored to different project sizes and budgets.

Data

Fortress Power eFlex 5.4 kWh Specifications

Total energy 5.4 kWh
Max. charge current (continuous) 100 A
Max. discharge current (continuous) 60 A
Max. pulse current (5 sec) 130 A
Capacity 105 Ah
Voltage range 48–55 V
Charging temperature 32°F to 113°F
Discharging temperature 32°F to 140°F
Storage temperature 32°F to 95°F
Dimensions (L×W×H) 21.5 × 17.5 × 7.2 in
Weight 116 lbs
Life cycles 6,000 @ 80% DoD

Backed by a 7-year warranty. UL9540 and UN38.3 certified.

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Free shipping on all orders within the mainland US (Hawaii, Alaska and overseas territories excluded - a freight forwarder is required). Orders are confirmed by email immediately; we verify stock with the supplier before your card is charged. In-stock items ship within five business days, with tracking emailed within 24 hours of shipment. Typical lead time from purchase to delivery is 5-10 business days; freight transit is usually 4-6 business days. Minimum order value is $69.

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You have 30 days from the delivery date to initiate a return (35 days for orders placed Nov 25-30 and Dec 25-31). Items must be unused, in original packaging with tags attached, and returns require prior authorization from our team.

  • Damaged on arrival or wrong item: contact us within 24 hours of delivery (photos help) - we cover return shipping and issue a full refund or replacement.
  • Manufacturing defects: covered under the manufacturer's warranty - contact us for guidance.
  • Changed your mind: return shipping is the customer's responsibility and a 25% restocking fee may apply.
  • Cancelling before shipment: a 3% deduction covers platform fees.
  • Refunds are processed to the original payment method within approximately 10 days of the return being received and inspected.

To start a return: +1 (307) 317-7213, hello@ecosolarkits.com, or live chat. Read the full return and refund policy