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Fortress Power 5KwH Lithium Iron Phosphate Battery | Deep Cycle Solar Battery (SOLD OUT)

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SKU: LFP-5K-48V
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*In Stock & Ready To Ship! Limited Supply. Order Yours Today!*

 Reliability and safety, the two things that Fortress is known for the most.  Their Lithium Iron Phosphate batteries are use the safest lithium technology to keep your family safe.  Not to mention that the advanced Lithium Ferro Phosphate (LFP) technology they use operates a wider temperature range to provide the most dependable performance on the market today.  Its super small design footprint makes it very space efficient for an easy installation.

 

Fortress Power Lithium Iron Phosphate Battery LFP-5K-48V (SOLD OUT)


This High-Performance Fortress Lithium Battery is easy to install, safe, and consistently reliable. It provides the lowest lifetime energy cost for both new solar customers and retrofit customers with over 6000 life cycles!  Fortress Lithium Batteries have a Battery Management System that integrates automatically to help deal with the most common battery problems: 
• Overcharge and Deep Discharge Protection
• Voltage and Temperature Observation
• Cell Monitoring and Balancing
• Built-in accessible 125 Amp DC breaker On/Off switch



Fortress Power 5KwH Lithium Iron Phosphate Battery Specs:

  •  Max. Charge Current (Continuous) [A]: 80
  •  Max. Discharge Current (Continuous) [A]: 80
  •  Max. Pulse Current (for 5 sec) [A]: 180
  •  Capacity [Ah]: 100
  •  Voltage Range [V]: 44-58.4
  •  Charging Temperature [F]: 32 to 113
  •  Discharging Temperature [F]: 32 to 140
  •  Storage Temperature [F]: 41 to 113
  •  Dimension [H x W x D, inch]: 20 x 9 x 26.5
  •  Life Cycles 6000: @ 80% DoD
  •  Round Trip Efficiency >98% 

More 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: 41 to 113 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

Fortress Lithium Battery is Easy to Integrate with Solar or Operate Independently to Provide Your Home Power Day or Night:
• Keep your solar system operating during a power outage
• Use energy stored during daytime for powering your home at night
• Lower your electric bill by avoiding the need to buy electricity at peak times
• Curtail demand charge for your business
• No maintenance and operation costs
• 30% investment tax credit available when used with solar
 
High Performance:
• Large power capacity, with a fast
charging and continuous discharge
power, creating an 98% round-trip
conversion.

Consistent Reliability:
• The advanced Lithium Ferro Phosphate
(LFP) technology operates a wider
temperature range to provide the most
dependable performance.

Superior Safety
• Manufactured at the highest standards.
LFP is proven to be one of the safest
Lithium technologies in the industry.

Easy to Install
• The compact design saves space and
can be conveniently installed. 

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

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

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

 Reliability and safety, the two things that Fortress is known for the most.  Their Lithium Iron Phosphate batteries are use the safest lithium technology to keep your family safe.  Not to mention that the advanced Lithium Ferro Phosphate (LFP) technology they use operates a wider temperature range to provide the most dependable performance on the market today.  Its super small design footprint makes it very space efficient for an easy installation.

 

Fortress Power Lithium Iron Phosphate Battery LFP-5K-48V (SOLD OUT)


This High-Performance Fortress Lithium Battery is easy to install, safe, and consistently reliable. It provides the lowest lifetime energy cost for both new solar customers and retrofit customers with over 6000 life cycles!  Fortress Lithium Batteries have a Battery Management System that integrates automatically to help deal with the most common battery problems: 
• Overcharge and Deep Discharge Protection
• Voltage and Temperature Observation
• Cell Monitoring and Balancing
• Built-in accessible 125 Amp DC breaker On/Off switch



Fortress Power 5KwH Lithium Iron Phosphate Battery Specs:

  •  Max. Charge Current (Continuous) [A]: 80
  •  Max. Discharge Current (Continuous) [A]: 80
  •  Max. Pulse Current (for 5 sec) [A]: 180
  •  Capacity [Ah]: 100
  •  Voltage Range [V]: 44-58.4
  •  Charging Temperature [F]: 32 to 113
  •  Discharging Temperature [F]: 32 to 140
  •  Storage Temperature [F]: 41 to 113
  •  Dimension [H x W x D, inch]: 20 x 9 x 26.5
  •  Life Cycles 6000: @ 80% DoD
  •  Round Trip Efficiency >98% 

More 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: 41 to 113 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

Fortress Lithium Battery is Easy to Integrate with Solar or Operate Independently to Provide Your Home Power Day or Night:
• Keep your solar system operating during a power outage
• Use energy stored during daytime for powering your home at night
• Lower your electric bill by avoiding the need to buy electricity at peak times
• Curtail demand charge for your business
• No maintenance and operation costs
• 30% investment tax credit available when used with solar
 
High Performance:
• Large power capacity, with a fast
charging and continuous discharge
power, creating an 98% round-trip
conversion.

Consistent Reliability:
• The advanced Lithium Ferro Phosphate
(LFP) technology operates a wider
temperature range to provide the most
dependable performance.

Superior Safety
• Manufactured at the highest standards.
LFP is proven to be one of the safest
Lithium technologies in the industry.

Easy to Install
• The compact design saves space and
can be conveniently installed. 

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

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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