The Hymotion / A123 Systems Conversion Module for the Toyota Prius

Do you own a 2004 to 2009 Toyota Prius? These are the models years that can be converted to plug-in capability using the kit sold by Hymotion / A123 Systems. Hymotion started this business and then were later bought by A123 Systems, makers of Nanophospate Lithium ion battery cells. Their product is now a drop-in 5 kWh Lithium ion battery pack that works in conjunction with the Toyota Hybrid Synergy drive and allows the operator to drive in an all EV mode.

During installation, an EV switch is installed that lets the driver operate entirely on electrical energy without the ICE starting. The Prius can then travel about 15 or so miles using the additional battery pack and also boasts 100 mpg over the course of 40 miles. The 40 mile number is significant as it represents the maximum number of miles traveled by the majority of US commuters.

The Hymotion unit costs $9995 installed and is really one of the best aftermarket kits available to make your Prius a plug-in. Here are some specifics from the Hymotion web site:

"A123 Hymotion L5 Plug-in Conversion Modules are designed to convert Toyota Prius HEVs into PHEVs that can achieve up to 100 mpg for 30-40 miles*

Hymotion L5 animation here

Product Specifications

• Designed for Toyota Prius, model years 2004 – 2009
• ~ 5 kWh pack
• 5.5 hour charge time
• ~ 180 pounds
• Up to 100 mpg for 30-40 miles within electrically assisted driving range

• Meets strictest emissions standards in U.S.
• Crash tested to federal new vehicle standards
• $9995 – includes 3 year standard warranty and installation"

Of course, the difficult part of this upgrade is coughing up the 10 grand, especially in the ultra depressed financial times in which we find ourselves. However, in my opinion this is the best bang for the buck of ANY plug-in kit on the market.

In the future, I will look at other manufacturer's solutions to converting a late model Prius into a plug-in Prius. There are several options avaialble.