This book investigates the possibilities and challenges of electric conversion of an existing (used) combustion engine car as an alternative to buying a new electric car. The conversion is meant to be a DIY project that can be carried out by anyone with the capacity to learn all the skills necessary and with sufficient funds to own a car in the first place. Parts of or the whole project can be outsourced to machine shops or similar if there are areas where the knowledge or equipment of the builder is insufficient.

This type of conversion proves to be highly modular, where the selection of both car and components depends on budget, time, and knowledge. Brushed DC motors offer reliability at a low cost but with relatively low efficiency. A three-phase induction motor will be a more costly option but with the benefit of higher efficiency and power. The batteries that are deemed appropriate for the conversion are lead-acid and lithium-ion batteries. Lead-acid batteries are robust and have a low cost. However, their low energy density will result in a higher weight, making this type of battery best suited for a small car with short range. Lithium-ion batteries, which are used in commercial EVs, have a high energy density and lower weight. They come at a high cost, however, and they require individual monitoring of the cells' voltage to prevent potential failure.

The converted car will have to be registered as a modified vehicle in order to legally be used. The original total weight of the car cannot be exceeded during the conversion, and because of this, a car with low curb weight and high max load is preferable as a starting point.

The purpose of this book is to research the possibilities and challenges regarding the electric conversion of used cars for personal day-to-day use.