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Fortress Power 5.4kW Lithium Deep Cycle Solar Battery

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SKU: eFlex 5.4
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*Limited Supply. Order Yours Today!*

Quite possibly the most well made battery on the market, the eFlex 5.4 kWh lithium battery from Fortress Power comes with built-in wifi for remote monitoring and troubleshooting to compliment its 10 year warranty with the safe and premium prismatic Lithium-Iron-Phosphate cells.  It's expandable from 5.4 kWh to 81 kWh for whatever your application needs making this one of the most popular units in the Fortress line-up.

 

WATERPROOF AND SALTWATER RESISTANT

The aluminum cabinet that houses the high quality battery cells is IP 65 waterproof which will prevent salt water corrosion.

Specifications:

  • Total Energy: 5.376 kWh
  • Nominal Voltage: 51.2(48)V
  • Voltage Range: 45-58.4 V
  • Max. Charge Current(Continuous): 100 Amp
  • Max. Discharge Current(Continuous): 100 Amp
  • Recommend Storage temperature: 32 to 95 F
  • Charge temperature: 32 to 113 F
  • Capacity: 105 Amp-hour
  • Dimension(H x W x D): 7.2" x 17.5" x 21.5"
  • Weight: 116 lbs

 

 

Lowest cost per cycle!

High ound trip efficiency & >99% mixed with 6000+ lifecycles means that this is one of the best bangs for your buck when it comes to a lithium deep cycle battery. 

 

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Features:

High Durability and long-lasting: 10 Year Warranty with the safe and premium prismatic Lithium-Iron-Phosphate cells

Versatile Applications: Expandable from 5.4 kWh to 81 kWh for residential, commercial, railway, military and telecommunications applications

Lowest Cost Per Cycle: High energy throughout with exceptional life span (6000+ cycles) and hight round-trip efficiency (>99%)

Monitor from Anywhere: The battery has a built-in data storage Wi-Fi for remote monitoring and troubleshooting ability

Waterproof and saltwater resistant: The sleek-looking aluminum cabinet has IP65 waterproof rating to prevent salt-water corrosion


Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Are Compatible with most inverters!

The eFlex5.4 is compatible with most inverters on the market today, but customers have found the best pairing with the units below:

- Sol Ark

- Outback Radian Series

- Schneider Conext

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Compatible Inverters

Fortress Lithium Iron Phosphate batteries are designed to work with most 48VDC inverter and chargers available on the market. Below is a list of compatible inverters and chargers. 

Sol-Ark: AC or DC coupled

 8 KW & 12 KW Inverters 

Schneider: AC or DC coupled

Conext XW MPPT charge controller; Conext XW+/XW pro series 

Outback: AC or DC coupled

Skybox, FLEX max charge controller (48V), FLEXpower series (48V); Radian series (48V); FXR(A) and FXR (E) series (48V); GVFX and GVFX series (48V); 

Magnum: AC or DC coupled

MS 4448PAE; MS 4048-20B 

SMA: AC coupled

SUNNY ISLAND 4548-US/6048-US; SUNNY ISLAND 3.0M/4.4M/6.0H/8.0H 

Victron: DC coupled

Phoenix VE.Direct Inverter; MultiPlus and Quatro Inverter/Charger; Skylla-TG Charger; General; Color Control or Venus GX 

Morning Star: DC coupled 

TriStar MPPT 600V; TriStar MPPT; Tristar PWM 

Midnite Solar: DC coupled

Solar Classic 150, 200 & 250; Solar Classic 150, 200 & 250-SL

 

*In Stock & Ready To Ship! Limited Supply. Order Yours Today!*

Still have questions? Give us a call at 877-242-2792

 

Shipping Times Estimated delivery time for in-stock orders placed today is 5-10 business days. Due to the increase in demand for off-grid solar products in 2022, our average shipping times for most orders is currently 9-12 business days.

Shipments & Lead Times: We process all orders within 72 hours. From there, we do our best to ship as quickly as possible. Shipping times vary depending on the product and size of your order. We will send you your tracking information to the e-mail and/or phone number on file.

With the incredible demand for solar products, our average delivery time to your door is between 9-12 business days from date of order. However, for some products, shipping can be as fast as 5-7 business days to your door. Please check specific product pages for the most accurate information.

*As of the start of 2022 - our stock levels are healthy and shipments are moving relatively quickly. If you place an order for something that is not in stock, or is on backorder, our team will reach out to you within 24-72 hours of placing your order to determine how you would like to move forward.

If you have any questions, give us a call at 877-242-2792 or reach out via email / live chat.

Product Description

*Limited Supply. Order Yours Today!*

Quite possibly the most well made battery on the market, the eFlex 5.4 kWh lithium battery from Fortress Power comes with built-in wifi for remote monitoring and troubleshooting to compliment its 10 year warranty with the safe and premium prismatic Lithium-Iron-Phosphate cells.  It's expandable from 5.4 kWh to 81 kWh for whatever your application needs making this one of the most popular units in the Fortress line-up.

 

WATERPROOF AND SALTWATER RESISTANT

The aluminum cabinet that houses the high quality battery cells is IP 65 waterproof which will prevent salt water corrosion.

Specifications:

  • Total Energy: 5.376 kWh
  • Nominal Voltage: 51.2(48)V
  • Voltage Range: 45-58.4 V
  • Max. Charge Current(Continuous): 100 Amp
  • Max. Discharge Current(Continuous): 100 Amp
  • Recommend Storage temperature: 32 to 95 F
  • Charge temperature: 32 to 113 F
  • Capacity: 105 Amp-hour
  • Dimension(H x W x D): 7.2" x 17.5" x 21.5"
  • Weight: 116 lbs

 

 

Lowest cost per cycle!

High ound trip efficiency & >99% mixed with 6000+ lifecycles means that this is one of the best bangs for your buck when it comes to a lithium deep cycle battery. 

 

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Features:

High Durability and long-lasting: 10 Year Warranty with the safe and premium prismatic Lithium-Iron-Phosphate cells

Versatile Applications: Expandable from 5.4 kWh to 81 kWh for residential, commercial, railway, military and telecommunications applications

Lowest Cost Per Cycle: High energy throughout with exceptional life span (6000+ cycles) and hight round-trip efficiency (>99%)

Monitor from Anywhere: The battery has a built-in data storage Wi-Fi for remote monitoring and troubleshooting ability

Waterproof and saltwater resistant: The sleek-looking aluminum cabinet has IP65 waterproof rating to prevent salt-water corrosion


Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Are Compatible with most inverters!

The eFlex5.4 is compatible with most inverters on the market today, but customers have found the best pairing with the units below:

- Sol Ark

- Outback Radian Series

- Schneider Conext

Fortress Power 5.4kW Lithium Deep Cycle Solar Battery Compatible Inverters

Fortress Lithium Iron Phosphate batteries are designed to work with most 48VDC inverter and chargers available on the market. Below is a list of compatible inverters and chargers. 

Sol-Ark: AC or DC coupled

 8 KW & 12 KW Inverters 

Schneider: AC or DC coupled

Conext XW MPPT charge controller; Conext XW+/XW pro series 

Outback: AC or DC coupled

Skybox, FLEX max charge controller (48V), FLEXpower series (48V); Radian series (48V); FXR(A) and FXR (E) series (48V); GVFX and GVFX series (48V); 

Magnum: AC or DC coupled

MS 4448PAE; MS 4048-20B 

SMA: AC coupled

SUNNY ISLAND 4548-US/6048-US; SUNNY ISLAND 3.0M/4.4M/6.0H/8.0H 

Victron: DC coupled

Phoenix VE.Direct Inverter; MultiPlus and Quatro Inverter/Charger; Skylla-TG Charger; General; Color Control or Venus GX 

Morning Star: DC coupled 

TriStar MPPT 600V; TriStar MPPT; Tristar PWM 

Midnite Solar: DC coupled

Solar Classic 150, 200 & 250; Solar Classic 150, 200 & 250-SL

 

*In Stock & Ready To Ship! Limited Supply. Order Yours Today!*

Still have questions? Give us a call at 877-242-2792

 

Shipping & Delivery

Shipping Times Estimated delivery time for in-stock orders placed today is 5-10 business days. Due to the increase in demand for off-grid solar products in 2022, our average shipping times for most orders is currently 9-12 business days.

Shipments & Lead Times: We process all orders within 72 hours. From there, we do our best to ship as quickly as possible. Shipping times vary depending on the product and size of your order. We will send you your tracking information to the e-mail and/or phone number on file.

With the incredible demand for solar products, our average delivery time to your door is between 9-12 business days from date of order. However, for some products, shipping can be as fast as 5-7 business days to your door. Please check specific product pages for the most accurate information.

*As of the start of 2022 - our stock levels are healthy and shipments are moving relatively quickly. If you place an order for something that is not in stock, or is on backorder, our team will reach out to you within 24-72 hours of placing your order to determine how you would like to move forward.

If you have any questions, give us a call at 877-242-2792 or reach out via email / live chat.

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