As many of you may know, we only sell products here that we know to be tried and true. We believe in quality, sustainability, and efficiency, which is why we’d like to introduce to you Fortress Power’s Lithium batteries. 

Fortress Power is a US based company that uses Lithium Ferro Phosphate technology to make their batteries. LFP (Lithium Ferro Phosphate) batteries are on the rise and replacing others because of its technical advances and very high level of safety. 

See our comparisons and product offerings below.

How do LFP Batteries Compare to Others?

LFP

Lithium Ion

Lead-acid

Safety

LFP
Safest technology (no thermal runway)
Lithium Ion
Potential thermal runway
Lead Acid
Risk of harmful gases

Life Cycles

LFP
Up to 6,000 life cycles (10 year warranty)
Lithium Ion
3,000 life cycles
Lead Acid
500 life cycles

Installation

LFP
Easy one hour Installation
Lithium Ion
Easy Installation
Lead Acid
Multiple installations required with replacements

Maintenance

LFP
Little to no maintenance.
Lithium Ion
Little to no maintenance
Lead Acid
Require service every 3-6 months.Temperature control required

Depth of Discharge

LFP
100%
Lithium Ion
100%
Lead Acid
50%

Cost Analysis

LFP
Higher facial cost Lowest cost per stored and supplied kWh
Lithium Ion
Higher facial cost Lower cost per stored and supplied kWh
Lead Acid
Lower facial cost Highest cost per stored and supplied kWh

The Choice is Easy!

How Can I Use LFP Batteries?

Lead-acid batteries and generators have only one use: backup power.
 The long service life and deep cycling capabilities of LFP batteries will allow you to take full advantage of the following applications:

Battery Backup
Whether your power is coming from solar, wind, or a utility company, use Fortress LFP batteries as a backup to protect your home or business from outages

Self-Supply
Store excess solar energy produced during the day for powering your home at night

Time-Based Control
Lower your power bill by storing energy when utility rates are lowest and using it when rates are high

Demand Charge Curtailment
Lower the demand costs of your business

 

Fortress Power vs Other Lithium Competitors

At this point, the advantages that Lithium batteries hold over Lead-acid batteries are clear, but let’s take a closer look into Fortress LFP batteries specifically against other popular brands

Tesla

Solaredge + LG Chem

*AC coupling requires an additional PV inverter and has at least 5% more power loss

Technological Advantages of LFP Batteries

See a comparison of Lithium LFP batteries and Lithium NMC batteries (technology used by Tesla and other competing Lithium battery companies)

LFP vs NMC

Fortress - LFP

Others (i.e. Tesla, LG Chem) - NMC

Safety

Eco-friendly

Operating Temp

LFP: -4 – 140 oF

-4 – 140 oF

NMC: -4 – 140 oF

14 – 113 oF

Peak Power Output

LFP is greater than Lithium Ion

Rate of Capacity Loss

LFP is less than Lithium Ion

Life Cycles

LFP is greater than Lithium Ion

Can I Use Fortress Power Batteries with My Existing Equipment?

Yes! Fortress Power Batteries are easily integrated with new and existing PV systems. Click each brand below to view compatible units and configurations

Sol-ark 8k Inverter
Sol-ark 12k Inverter

AC or DC coupled

Conext XW MPPT charge controller
Conext XW+ series
Conext SW

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)

AC or DC coupled

MS 4448PAE
MS 4048-20B

AC or DC coupled

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

AC coupled

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

DC coupled

TriStar MPPT 600V
TriStar MPPT
Tristar PWM
MultiWave™ 4KW

DC coupled

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

DC coupled

Don’t see the inverter/charger you have? Contact us 

Fortress Power Batteries

Fortress Power LFP-5

Fortress Power LFP-5

Fortress Power’s High-Performance Lithium Battery is easy to install, safe, and consistently reliable. It provides the lowest lifetime  energy cost for both new solar and retrofit customers. 

Fortress Lithium Battery has the industry’s most advanced technology with a Battery Management System that integrates multilevel safety concepts:

  • Overcharge and deep discharge protection
  • Voltage and temperature observation
  • Cell monitoring and balancing
  • Built-in accessible 125 Amp DC breaker On/Off switch

The LFP-5k has a large power capacity, with fast charging and continuous discharge power, creating a 98% round-trip conversion. 

On Grid: Use as energy storage, whether your energy is coming from solar, wind, or a utility company, to protect your home or business from power outages. 

Off Grid: Backup power supply for your off grid energy system

AC Coupling to integrate into existing PV systems

DC Coupling to add to new PV systems or retrofit to an existing system with string inverters

Total Energy : 5.12 kWh

Max. Charge Current (continuous): 80 A

Max. Discharge Current (continuous): 100 A

Max. Pulse Current (for 5 seconds): 180 A

Capacity: 100 Ah

Nominal Voltage: 51.2 V

Voltage Range: 44 – 58.4 V

Charging Temperature: 32 – 113 oF

Discharging Temperature: -4 – 140 oF

Storage Temperature : 41-113 oF

Dimensions (HxWxD) : 9.4 x 26.5 x 20 inches

Weight: 130 lb

Enclosure Protection Rating: IP55

Mounting Options: Floor standing

Certificates: UL 1642, CE

Warranty: 5 year

Life Cycles: 6,000 at 80% DoD

Scaling: 3 in parallel

Battery Breaker: 125 A

Efficiency: >98%

Cost: $3,600

Fortress Power LFP-10

Fortress Power LFP-10

Fortress Power’s High-Performance Lithium Battery is easy to install, safe, and consistently reliable. It provides the lowest lifetime  energy cost for both new solar and retrofit customers. 

Fortress Lithium Battery has the industry’s most advanced technology with a Battery Management System that integrates multilevel safety concepts:

  • Overcharge and deep discharge protection
  • Voltage and temperature observation
  • Cell monitoring and balancing
  • Built-in accessible 125 Amp DC breaker On/Off switch

The LFP-10k has a large power capacity, with fast charging and continuous discharge power, creating a 98% round-trip conversion. 

On Grid: Use as energy storage, whether your energy is coming from solar, wind, or a utility company, to protect your home or business from power outages. 

Off Grid: Backup power supply for your off grid energy system

AC Coupling to integrate into existing PV systems

DC Coupling to add to new PV systems or retrofit to an existing system with string inverters

Total Energy : 10.4 kWh
Max. Charge Current (continuous): 80 A
Max. Discharge Current (continuous): 100 A
Max. Pulse Current (for 5 seconds): 180 A
Capacity: 200 Ah
Nominal Voltage: 51.2 (48) V
Voltage Range: 44 – 58.4 V
Charging Temperature: 32 – 113 oF (0 – 55 oC)
Discharging Temperature: -4 – 140 oF (0 – 65 oC)
Storage Temperature : 41-113 oF (5 – 55 oC)
Dimensions (HxWxD) : 31.4 x 17.3 x 9.4 inches (860 x 440 x 238 mm)
Weight: 210 lb (95 kg)
Enclosure Protection Rating: IP32 (indoor unit)
Mounting Options: Floor standing
Certificates: UL 1642, CE
Warranty: 10 years (5 years outside of US & Canada)
Life Cycles: 6,000 at 80% DoD
Scaling: 2 in parallel
Battery Breakers: 150 A
Round Trip Efficiency: >98%

Cost: $6,750

Fortress Power eVault 18.5

Fortress Power eVault 18.5

Fortress Power’s engineers are on a mission to provide you with the most advanced Lithium Iron Phosphate Battery available! Not only is the new Fortress eVault 18.5 kWh battery safe, long-lasting and affordable, but is also equipped with a brand new LCD screen that displays voltage, state of charge, remaining capacity and power output.

The built-in Battery Management System integrates multilevel safety concepts for excellent performance:

  • Overcharge and Deep Discharge Protection
  • Over Current Protection
  • Voltage and Temperature Monitoring
  • Over-heat protection
  • Cell Monitoring and Balancing

Fortress LFP batteries use the safest and most reliable technology, are easy to install, and are competitively priced with high round trip efficiency!

On Grid: Use as energy storage, whether your energy is coming from solar, wind, or a utility company, to protect your home or business from power outages. 

Off Grid: Backup power supply for your off grid energy system

AC Coupling to integrate into existing PV systems

DC Coupling to add to new PV systems or retrofit to an existing system with string inverters

Total Energy : 18.5 kWh
Capacity: 360 Ah
Recommended Charge Current: 100 A
Max. Charge Current (continuous): 170 A
Max. Discharge Current (continuous): 180 A
Max. Pulse Current (for 10 seconds): 200 A
Nominal Voltage: 51.2 (48) V
Voltage Range: 45 – 58.4 V
Life Cycles: 6,000 at 80% DoD
Charging Temperature: 32 – 113 oF
Discharging Temperature: 32 – 113 oF
Recommended Storage Temperature : 50 – 95 oF
Dimensions (HxWxD) : 38.8 x 19.2 x 21.3 inches
Weight: 476 lb
Enclosure Protection Rating: IP21
Mounting Options: Floor standing
Certificates: UL 1624
Warranty: 5 or 10 year
Scalability: Maximum 12 in parallel (222 kWh)
Communication: CAN/RS485
High Current Circuit Breaker: 250A
Efficiency: >98%

Cost: $12,420

Fortress + Solark

The Ultimate Energy Storage Solution

Finally, Affordable Battery Solar!

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