Blog Post

Drop-In Lead Acid Battery Replacement | Safe Reliable Off-Grid Power

Lead Acid Battery Replacement: An Off-Grid Winter Power Guide

A guide for choosing safe, reliable energy storage to replace lead acid batteries to provide off-grid power for your home.


SimpliPhi is the only lithium ion battery maker to offer a “drop in” lead acid replacement. This means that you will not have to change your existing inverters or other equipment when you swap out your batteries. The only change is the programmed settings in the inverter charge controller. Additionally, our batteries utilize similar terminal connections, which means your battery cables will also be compatible. SimpliPhi Power provides integration guides for the most popular off-grid inverters and charge controls. Changing out your lead acid batteries will require reprogramming your system, and our team is here to help you through this process to make the transition seamless.

That said, PHI batteries are significantly smaller, lighter and more efficient than lead acid batteries, meaning that your energy storage system will take up less room, weigh considerably less and provide more usable capacity in a smaller battery bank. One tiny home owner recently was able to replace eight lead acid batteries with three PHI 3.5 kWh LFP, eliminating more than 800 pounds of weight and recovering more than half the space required for her battery bank.


Unlike lead acid batteries, SimpliPhi’s energy storage solutions do not require ventilation or cooling and will not overheat. They are also safer than other lithium ion batteries because LFP does not contain cobalt, which is the source of toxicity, hazards and ‘thermal runaway’ associated with other lithium batteries. LFP is environmentally benign, non-toxic and safe for your home and family.

Off-Grid Residential SimpliPhi Solutions

Model Type Features
PHI Batteries

Click image for more info.

Hard wired*
  • Modular batteries that can be combined to create a battery bank of any size to power any electricity load
AccESS Energy Storage System

Click image for more info.

Turn-key hard wired*
  • Back up whole-home power solution that includes all the PHI battery and inverter equipment you need in one enclosure
  • NEMA-3R rated cabinet can be installed indoors or outdoors

*Initial installation by a licensed C10 or C46 electrician required

SimpiPhi’s applications engineers and I.Q. Certified Installers can help you calculate how much energy storage capacity you will need and what solution is best for you. Our storage solutions have been proven in the field for a decade, including by the U.S. military in Iraq and Afghanistan.

Contact Us