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The PHI 3.5™ kWh 60 Amp deep-cycle Lithium Ferro Phosphate (LFP) battery is optimized with proprietary cell architecture, power electronics, BMS and assembly methods. It is modular, light- weight and scalable for installations that range from kWh to MWh. Provides power security and seamless integration of renewable and traditional sources of energy in conjunction with or independent of the grid: net zero, peak shaving, emergency back-up, portable and mobile.

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  • Built-in accessible 80 Amp DC breaker On/Off switch – increases safety and simplifies installations
  • 24V and 48V LFP batteries with proprietary architecture and Battery Management
    System (BMS)—do not require ventilation, cooling or thermal regulation
  • Compatible with all industry standard inverter/charge controllers
  • Drop in replacement for lead acid
  • LFP is the safest, most environmentally benign Lithium Ion chemistry available—no risk of thermal runaway or fire
  • No AC or toxic liquid cooling – negligible parasitic drain – long cycle life
  • Non-toxic and non-hazardous recyclable materials


“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 3.5TM24V48V
DC Voltages – Nominal25.651.2
Amp Hours13869
Rated Wh Capacity @ C/23.5 kWh3.5 kWh
Max Discharge Current60 Amps (10 mins)60 Amps (10 mins)
Max Contin. Disch. Current45 Amps34 Amps
Max Contin. Charge Current45 Amps34 Amps
DC Voltage Range120 to 28.840 to 57.6
Depth of Discharge1up to 100%up to 100%
Operating Efficiency98%98%
Operating Temp1-4° to 140°F (-20° to 60°C)-4° to 140°F (-20° to 60°C)
Charge Temp32° to 120°F (0° to 49°C)32° to 120°F (0° to 49°C)
Self-Discharge Rate<1% loss per month<1% loss per month
Cycle Life10,000+10,000+
Memory EffectNoneNone
Warranty Period10 Years10 Years
Weight77.5 lbs (35.15 kg)77.5 lbs (35.15 kg)
Dimensions13.5 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)
  • 1. Max operating conditions. Refer to warranty for recommended conditions.
  • All specifications listed are typical/nominal and subject to change without notice
  • UN3480, Lithium Ion batteries, 9, II
  • UL, CE, UN/DOT and RoHS compliant components – UL Certified
  • Designed and built in California, USA


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