Click to Download PDF Specification Sheet

SimpliPhi Power’s PHI 3.8-MTM Battery utilizes the safest Lithium Ion chemistry available, Lithium Ferro Phosphate (LFP). No cobalt or explosive hazards that put customers at risk. By eliminating cobalt, the risk of thermal runaway, fire propagation, operating temperature constraints, and toxic coolants are reduced. When combined with our integrated high-performance Battery Management System (BMS), accessible 80A DC breaker On/Off switch and overcurrent protection (OCPD), the PHI 3.8-M Battery delivers safe, highly efficient and cost-effective service over the life of both residential and commercial installations, on or off-grid. Compatible with all industry-standard inverter charge controllers, the PHI 3.8-M Battery supports balance-of-system equipment and optimizes any power generation source – solar, wind, grid, generator – with scalable, on-demand energy storage solutions for critical back-up and daily savings on electricity bills.

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CHEMISTRY Lithium Ferro Phosphate (LFP)
The safest Lithium Ion chemistry available
No cobalt, risk of thermal runaway or fire
OCPD Built-in accessible 80 Amp DC breaker On/Off switch
BMS Built-in Battery Management System
COMPATIBILITY Compatible with all industry standard inverters and charge controllers
Battery bank-to-inverter output sizing must adhere to a 2:1 ratio:
battery quantity = (inverter kWAC rating ÷ inverter efficiency)
÷ battery MAX Continuous Discharge Rate in kWDC
MAINTENANCE Maintenance-free
No ventilation, cooling or thermal regulation required


“We are extremely happy with the decision to switch to SimpliPhi (PHI 3.5s) and love the reduction of footprint and weight, as well as the dramatically lengthened warranty and life expectancy.”
Ty T., Tiny House Owner Florida – August 2018

“We’ve been super impressed with how these work. These were a very easy install. They’re also completely scalable. That’s the neat thing about these SimpliPhi batteries – that as we grow with the project, as they add more things, which happens from the beginning of a project, it’s scalable – we just keep adding more batteries to this system.”
Jason Andrade of West Coast Sustainables, California – August 2018

“We like these batteries because of their relatively compact size and weight, safety, ability to charge and discharge at a high rate and their life expectancy.”
Scott Murakami, Hawaiian Outpost – November 2017

“(This system) provides the homeowner with a drastic reduction in their electric bill as well as the ability to live comfortably in any power outage situation.”
Appalachian Energy Solutions, North Carolina – November 2017


PHI 3.8-M™ 24V 48V
DC Voltages – Nominal 25.6VDC 51.2VDC
Amp-Hours 151 Ah 75 Ah
Rated kWh Capacity @ C/2 3.8 kWh DC @ 100% DOD
3.04 kWh DC @ 80% DOD
3.8 kWh DC @ 100% DOD
3.04 kWh DC @ 80% DOD
MAX Discharge Rate (10 minutes) 80 Amps DC (2.05 kW DC) 80 Amps DC (4.1 kW DC)
MAX Continuous Discharge Rate 75 Amps DC (1.9 kW DC) 37.5 Amps DC (1.92 kW DC)
MAX Continuous Charge Rate 75 Amps DC (1.9 kW DC) 37.5 Amps DC (1.92 kW DC)
DC Voltage Range1 24 VDC to 28 VDC 48 VDC to 56 VDC
Depth of Discharge1 up to 100% up to 100%
Operating Efficiency 98% 98%
Charge Temperature1 32° to 120°F (0° to 49°C) 32° to 120°F (0° to 49°C)
Operating Temperature1 -4° to 140°F (-20° to 60°C) -4° to 140°F (-20° to 60°C)
Storage Temperature1 6 months: 14° to 77° F (-10° to 25° C)
3 months: -4° to 113° F (-20° to 45° C)
6 months: 14° to 77° F (-10° to 25° C)
3 months: -4° to 113° F (-20° to 45° C)
Self-Discharge Rate <1% loss per month <1% loss per month
Cycle Life 10,000+ (@80% DOD) 10,000+ (@80% DOD)
Memory Effect None None
Warranty Period 10 Years 10 Years
Weight 86 lbs. (39.0 kg) 86 lbs. (39.0 kg)
Dimensions 13.5 x 14 x 8 in. (15.5” H w/terminals) / 0.88 ft3
(34.3 x 35.6 x 20.3 cm / 0.025 m3)
13.5 x 14 x 8 in. (15.5” H w/terminals) / 0.88 ft3
(34.3 x 35.6 x 20.3 cm / 0.025 m3)
Model Number PHI3.8 24V 60 VTE BRK PHI3.8 48V 60 VTE BRK

1. Max operating conditions. Refer to Installation Manual for recommended conditions.

  • All specifications listed are typical/nominal and subject to change without notice.
  • UN 3480, Lithium Ion battery contained in equipment, 9, II
  • UL, CE, UN/DOT and RoHS compliant components – UL Certified
  • Designed and manufactured in California, USA


SimpliPhi PHI Battery Product Series Overview

Be Green Solar Demonstrates Lead Acid Battery Replacement with SimpliPhi Power Batteries

How to Connect a Lug to the Terminals on a SimpliPhi Power Battery

Connecting a Busbar to Terminals on a SimpliPhi Battery

Paralleling PHI Batteries with Threaded Studs Using Battery Cables

Paralleling PHI Batteries Using Busbars

How to Commission a DC Coupled Battery System


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