- Rugged, Long-lasting, Daily Use Battery
- Safe Lithium Iron Phosphate Technology (LifeP04)
- 98% Round Trip Efficiency
- Flexible Mounting Options
- Remote Monitoring Including Wifi, Modbus, and Canbus
- BMS Monitors & Balances Individual Cells
- NRTL tested to UL9540 and UL9540a standards
eFlex 5.4kWh LFP Battery
eFlex 5.4kWh LFP Battery
Description
- Rugged, Long-lasting, Daily Use Battery
- Safe Lithium Iron Phosphate Technology (LifeP04)
- 98% Round Trip Efficiency
- Flexible Mounting Options
- Remote Monitoring including wifi, modbus, and canbus
- BMS Monitors & Balances Individual Cells
- NRTL certified to UL9540 and UL9540a standards
Product Info
Have questions? Email: [email protected]
Product can be paired with most chargers and hybrid inverters
available on the market.
General
| Name | eFlex 5.4 |
| Total Energy(kWh) | 5.4 |
| Max. Charge Current (Continuous) [A] | 100 |
| Max. Discharge Current (Continuous) [A] | 60 |
| Max. Pulse Current (for 5 sec) [A] | 130 |
| Capacity [Ah] | 105 |
| Voltage Range [V] | 48-55 |
| Charging Temperature [F] | 32 to 113 |
| Discharging Temperature [F] | 32 to 140 |
| Storage Temperature [F] | 32 to 95 |
| Dimension [L x W x H, inch] | 21.5 x 17.5 x 7.2 |
| Weight [lbs] | 116 |
| Life Cycles | 6000 @ 80% DoD |
| Round Trip Efficiency | >98% |
7 reviews for eFlex 5.4kWh LFP Battery
Overview
- Rugged, Long-lasting, Daily Use Battery
- Safe Lithium Iron Phosphate Technology (LifeP04)
- 98% Round Trip Efficiency
- Flexible Mounting Options
- Remote Monitoring Including Wifi, Modbus, and Canbus
- BMS Monitors & Balances Individual Cells
- NRTL tested to UL9540 and UL9540a standards
Specifications
General
| Name | eFlex 5.4 |
| Total Energy(kWh) | 5.4 |
| Max. Charge Current (Continuous) [A] | 100 |
| Max. Discharge Current (Continuous) [A] | 60 |
| Max. Pulse Current (for 5 sec) [A] | 130 |
| Capacity [Ah] | 105 |
| Voltage Range [V] | 48-55 |
| Charging Temperature [F] | 32 to 113 |
| Discharging Temperature [F] | 32 to 140 |
| Storage Temperature [F] | 32 to 95 |
| Dimension [L x W x H, inch] | 21.5 x 17.5 x 7.2 |
| Weight [lbs] | 116 |
| Life Cycles | 6000 @ 80% DoD |
| Round Trip Efficiency | >98% |
Downloads
Video
Reviews (7)
7 reviews for eFlex 5.4kWh LFP Battery
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Excellent product and service!!!
-
Edwin gave Fortress Power an AWESOME Recommendation
-
Alain was knowledgeable, patient and thorough as he helped me update the firmware for the Fortress batteries in a remote off grid setting. I really appreciated him taking the time to make sure everything was working correctly.
-
Wow!! What a dream to install! Fortress new 18.5kWh E-VAULT ROCKS!! it totally goes in easy, lots of room in the wiring compartment and it just “makes sense” intuitively. Heck, this one is backing up the whole (quite large) residence using two SolArk inverter’s. SolArk pairs brilliantly with Fortress. Their support line is very helpful and they actually answer the phone. They are priced competitively believe it or not (LFP this high quality is WORTH the investment when you analyze LCOE across it’s…
-
Jing suggests you use Fortress Power
-
These batteries are the best! I’d add an extra star to the rating if I could! My brother is the genius of the family (ex rocket-scientist and ex nuclear physicist), and he installs solar worldwide where he works. He recommended that I look into Fortress’s new modular batteries, and everytime I’ve listened to his recommendations, things worked out great! He recommended that I check out the new modular batteries from Fortress, so I did. He told me that they had excellent customer support and quality, and they do! He told me that Lithium Iron Phosphate (LFP or LiFePO4) is the safest lithium technology, so it won’t blow up or catch fire from thermal runaway like old lithium ion technology, and that lithium batteries are much more cost effective over their lifetime than lead acid, even though they cost more upfront. I found that Fortress had just introduced the eFlex 5.4 batteries, and they had good specs and warranty, so I ordered some. Tech support was extremely helpful, even checking the electrical characteristics for the flat bar copper that I was planning to use for bus bars across the battery bank.
The shipping company soaked the boxes and destroyed all four sides of the pallet that they were on, so I was worried at first, but everything was very well packed and protected. Only a few spare connectors in a ziplock bag got wet. Everything else was dry even though there was an inch of water puddled in the packing above the batteries. The batteries were all good. I was so relieved! And they’re designed so well they look like waterproof – like they’re built for powering boats! It was being able to connect up power with the batteries all powered off and safe to touch, then push the button on the battery to power the circuit.
I also like the LEDs on the front panel. You can easily see that they’re powered up, how full they are, and whether they’re charging and discharging at a glance.
I replaced a rack of OutBack high capacity lead acid batteries that failed after 4 years, which was double the warranty, but stillthey were constantly kept 80% to 100% charged. They never performed as well as my eFlex 5.4 batteries that I’ve had for a year now. After several months of using absolutely no grid, electric company stopped by to see if there was a problem. We disconnected their grid soon after, once we got a suitable generator for backup. We only used our generator to charge the batteries when the house flooded and we needed to constantly run dehumidifiers. We have only been using about half a cycle per month, too, so they should last a long time!
We’re so impressed with these batteries, we’re having some installed in our son’s place as he does his solar. The batteries have the ability to communicate with newer inverter & charge controller equipment for more efficient operation. (the charge controller doesn’t need to wait to see the voltage start to drop before charging to offset usage, and can better estimate how much charging the batteries need by querying them directly rather than modeling the battery bank through some other device, and that means even fewer cycles, which translates to longer battery life)
-
These batteries are the best! I’d add an extra star to the rating if I could! My brother is the genius of the family (ex rocket-scientist and ex nuclear physicist), and he installs solar worldwide where he works. He recommended that I look into Fortress’s new modular batteries, and every time I’ve listened to his recommendations, things worked out great! When he recommended that I check out the new modular batteries from Fortress, I did. He told me that they had excellent customer support and quality, and they do! He told me that Lithium Iron Phosphate (LFP or LiFePO4) is the safest lithium technology, so it won’t blow up or catch fire from thermal runaway like old lithium ion technology, and that lithium batteries are much more cost effective over their lifetime than lead acid, even though they cost more upfront. I found that Fortress had just introduced the eFlex 5.4 batteries, and they had good specs and warranty, so I ordered some. Tech support was extremely helpful, even checking the electrical characteristics for the flat bar copper that I was planning to use for bus bars across the battery bank.
The shipping company soaked the boxes and destroyed all four sides of the pallet that they were on, so I was worried at first, but everything was very well packed and protected. Only a few spare connectors in a ziplock bag got wet. Everything else was dry even though there was an inch of water puddled in the packing above the batteries. The batteries were all good. I was so relieved! And they’re designed so well they look like waterproof – like they’re built for powering boats! It was really nice being able to connect up power with the batteries all powered off and safe to touch, then push the button on the battery to power the circuit.
I also like the LEDs on the front panel. You can easily see that they’re powered up, how full they are, and whether they’re charging and discharging at a glance.
I replaced a rack of OutBack high capacity lead acid batteries that failed after 4 years, which was double the warranty, but stillthey were constantly kept 80% to 100% charged. They never performed as well as my eFlex 5.4 batteries that I’ve had for a year now. After several months of using absolutely no grid, electric company stopped by to see if there was a problem. We disconnected their grid soon after, once we got a suitable generator for backup. We only used our generator to charge the batteries when the house flooded and we needed to constantly run dehumidifiers. We have only been using about half a cycle per month, too, so they should last a long time!
We’re so impressed with these batteries, we’re having some installed in our son’s place as he does his solar. The batteries have the ability to communicate with newer inverter & charge controller equipment for more efficient operation. (the charge controller doesn’t need to wait to see the voltage start to drop before charging to offset usage, and can better estimate how much charging the batteries need by querying them directly rather than modeling the battery bank through some other device, and that means even fewer cycles, which translates to longer battery life)
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Carlos del Río (verified owner) –
Excellent product and service!!!
Edwin J (verified owner) –
Edwin gave Fortress Power an AWESOME Recommendation
Ed Witkin (verified owner) –
Alain was knowledgeable, patient and thorough as he helped me update the firmware for the Fortress batteries in a remote off grid setting. I really appreciated him taking the time to make sure everything was working correctly.
MiJo Nels (verified owner) –
Wow!! What a dream to install! Fortress new 18.5kWh E-VAULT ROCKS!! it totally goes in easy, lots of room in the wiring compartment and it just “makes sense” intuitively. Heck, this one is backing up the whole (quite large) residence using two SolArk inverter’s. SolArk pairs brilliantly with Fortress. Their support line is very helpful and they actually answer the phone. They are priced competitively believe it or not (LFP this high quality is WORTH the investment when you analyze LCOE across it’s…
Jing Y (verified owner) –
Jing suggests you use Fortress Power
Ted S –
These batteries are the best! I’d add an extra star to the rating if I could! My brother is the genius of the family (ex rocket-scientist and ex nuclear physicist), and he installs solar worldwide where he works. He recommended that I look into Fortress’s new modular batteries, and everytime I’ve listened to his recommendations, things worked out great! He recommended that I check out the new modular batteries from Fortress, so I did. He told me that they had excellent customer support and quality, and they do! He told me that Lithium Iron Phosphate (LFP or LiFePO4) is the safest lithium technology, so it won’t blow up or catch fire from thermal runaway like old lithium ion technology, and that lithium batteries are much more cost effective over their lifetime than lead acid, even though they cost more upfront. I found that Fortress had just introduced the eFlex 5.4 batteries, and they had good specs and warranty, so I ordered some. Tech support was extremely helpful, even checking the electrical characteristics for the flat bar copper that I was planning to use for bus bars across the battery bank.
The shipping company soaked the boxes and destroyed all four sides of the pallet that they were on, so I was worried at first, but everything was very well packed and protected. Only a few spare connectors in a ziplock bag got wet. Everything else was dry even though there was an inch of water puddled in the packing above the batteries. The batteries were all good. I was so relieved! And they’re designed so well they look like waterproof – like they’re built for powering boats! It was being able to connect up power with the batteries all powered off and safe to touch, then push the button on the battery to power the circuit.
I also like the LEDs on the front panel. You can easily see that they’re powered up, how full they are, and whether they’re charging and discharging at a glance.
I replaced a rack of OutBack high capacity lead acid batteries that failed after 4 years, which was double the warranty, but stillthey were constantly kept 80% to 100% charged. They never performed as well as my eFlex 5.4 batteries that I’ve had for a year now. After several months of using absolutely no grid, electric company stopped by to see if there was a problem. We disconnected their grid soon after, once we got a suitable generator for backup. We only used our generator to charge the batteries when the house flooded and we needed to constantly run dehumidifiers. We have only been using about half a cycle per month, too, so they should last a long time!
We’re so impressed with these batteries, we’re having some installed in our son’s place as he does his solar. The batteries have the ability to communicate with newer inverter & charge controller equipment for more efficient operation. (the charge controller doesn’t need to wait to see the voltage start to drop before charging to offset usage, and can better estimate how much charging the batteries need by querying them directly rather than modeling the battery bank through some other device, and that means even fewer cycles, which translates to longer battery life)
Ted S –
These batteries are the best! I’d add an extra star to the rating if I could! My brother is the genius of the family (ex rocket-scientist and ex nuclear physicist), and he installs solar worldwide where he works. He recommended that I look into Fortress’s new modular batteries, and every time I’ve listened to his recommendations, things worked out great! When he recommended that I check out the new modular batteries from Fortress, I did. He told me that they had excellent customer support and quality, and they do! He told me that Lithium Iron Phosphate (LFP or LiFePO4) is the safest lithium technology, so it won’t blow up or catch fire from thermal runaway like old lithium ion technology, and that lithium batteries are much more cost effective over their lifetime than lead acid, even though they cost more upfront. I found that Fortress had just introduced the eFlex 5.4 batteries, and they had good specs and warranty, so I ordered some. Tech support was extremely helpful, even checking the electrical characteristics for the flat bar copper that I was planning to use for bus bars across the battery bank.
The shipping company soaked the boxes and destroyed all four sides of the pallet that they were on, so I was worried at first, but everything was very well packed and protected. Only a few spare connectors in a ziplock bag got wet. Everything else was dry even though there was an inch of water puddled in the packing above the batteries. The batteries were all good. I was so relieved! And they’re designed so well they look like waterproof – like they’re built for powering boats! It was really nice being able to connect up power with the batteries all powered off and safe to touch, then push the button on the battery to power the circuit.
I also like the LEDs on the front panel. You can easily see that they’re powered up, how full they are, and whether they’re charging and discharging at a glance.
I replaced a rack of OutBack high capacity lead acid batteries that failed after 4 years, which was double the warranty, but stillthey were constantly kept 80% to 100% charged. They never performed as well as my eFlex 5.4 batteries that I’ve had for a year now. After several months of using absolutely no grid, electric company stopped by to see if there was a problem. We disconnected their grid soon after, once we got a suitable generator for backup. We only used our generator to charge the batteries when the house flooded and we needed to constantly run dehumidifiers. We have only been using about half a cycle per month, too, so they should last a long time!
We’re so impressed with these batteries, we’re having some installed in our son’s place as he does his solar. The batteries have the ability to communicate with newer inverter & charge controller equipment for more efficient operation. (the charge controller doesn’t need to wait to see the voltage start to drop before charging to offset usage, and can better estimate how much charging the batteries need by querying them directly rather than modeling the battery bank through some other device, and that means even fewer cycles, which translates to longer battery life)