Using Nonconductive Coatings as Part of an EV Conversion
Electric vehicles (EVs) are gaining popularity, and internal combustion engine vehicles are increasingly being converted to electric power by individuals and companies. Quality engineering and skillful installation are a must for a safe, great-running conversion. Because the original vehicle was never engineered with a high-voltage motor system in mind, it needs to be properly prepared before EV components are installed. A critical part of that preparation is ensuring the surfaces on which high-voltage components are mounted are non-conductive. Here we'll discuss using non-conductive coatings as part of an EV conversion and why RustSeal is an excellent choice for the job.
Non-Conductive Coatings Ensure Safety and Proper Function of EV Electrical Systems
Non-conductive coatings isolate EV electrical components from accidental electrical connections to one another through the chassis, body, and other parts of the vehicle. The coatings provide a barrier of insulation to prevent short circuits or unintended electrical paths, helping ensure safe and correct function throughout the EV conversion.
Why Electrical Isolation Matters In a converted EV, the chassis and body panels can become unintended conductors between high-voltage components like the motor, battery pack, and controller. Even a small unintended current path can cause component damage, system faults, or a serious safety hazard. A quality non-conductive coating creates a reliable insulating barrier between metal surfaces and electrical components. |
What Makes a Coating Non-Conductive?
Nothing will make metal itself non-conductive, but a properly formulated coating will prevent the flow of electric current between different metal components and surfaces. Non-conductive coatings are formulated with materials like epoxies, polyurethanes, aluminum oxide, and silica — all of which have high electrical resistivity and impede the flow of electric charges.
Avoid These Conductive Materials Coatings formulated with graphite, metallic flakes, or metal oxides are conductive and should never be used to insulate surfaces for an EV conversion. Always confirm a coating's formulation before applying it near high-voltage components. |
Areas to Apply Non-Conductive Coatings During an EV Conversion
When performing an EV conversion, non-conductive coatings can be applied to insulate metal surfaces including:
- Frames and subframes
- Battery boxes and enclosures
- Engine and motor compartments
- Floor pans
- Vehicle body panels near electrical components
In general, any metal surface that comes into close proximity to electrical components — motors, batteries, controllers, or wiring — is a candidate for a non-conductive coating.
RustSeal: A Durable Non-Conductive Coating for EV Conversions
When preparing a vehicle for EV system installation, RustSeal performs as a durable, non-conductive coating. RustSeal seals and encapsulates metal to provide a rock-hard, ceramic-like barrier that insulates metal from electricity, resists chipping and scratching, and will not crack or peel.
RustSeal is a single-part, moisture-cured urethane (MCU) rust preventive coating with inherent non-conductive properties. Urethane is recognized as an excellent insulating material, making RustSeal a natural fit for EV insulation applications. It is highly resistant to abrasion and chemicals, hard yet flexible enough to withstand impacts, self-leveling, and available in a wide range of colors. RustSeal can be brushed, rolled, or sprayed.
Important: Avoid Galvanized and Silver Colors for EV Work RustSeal in Galvanized or Silver color contains metallic flakes and is therefore conductive. These colors must not be used to insulate metal surfaces in an EV conversion. All other RustSeal colors are formulated without metallic additives and are appropriate for EV insulation use. |
How to Apply RustSeal for an EV Conversion
With proper surface preparation, RustSeal can be applied directly to prepared bare metal, treated surface rust, or over existing paints and coatings.
Application to Bare Metal and/or Surface Rust
- Remove loose or flaky rust with 320-grit sandpaper, a wire brush, or wire wheel to achieve a solid surface profile.
- Remove all surface contamination — even fingerprints or slight grease residue can compromise adhesion. Wash the surface with KBS Klean, a water-based concentrate that removes contaminants without leaving a residue.
- Scrub the surface with RustBlast, a powerful rust remover, zinc phosphate pre-primer, and metal etch.
- Apply RustSeal with a minimum of 3 thin covering coats at approximately 2 mils each.
Pro Tip: You Don't Need to Remove Every Bit of Rust It is not necessary to remove every trace of rust before applying RustSeal. RustSeal is formulated to bond to and permanently seal any remaining flash rust or corrosion — focus on removing loose, flaky material and let RustSeal handle the rest. |
Application Over an Existing Paint or Coating
For the best possible performance, remove all old paint via chemical or mechanical stripping, then follow the KBS Klean and RustBlast prep process before applying RustSeal.
When full stripping is not practical, RustSeal can be applied over an existing painted surface after lightly scuffing with 320-grit sandpaper and cleaning with KBS Klean. This still delivers an extremely durable, moisture-resistant, and insulative coating.
Frequently Asked Questions
Is RustSeal truly non-conductive? Yes. RustSeal is formulated with urethane, which has high electrical resistivity. It does not contain graphite, metallic flakes, or metal oxides, making it non-conductive in all colors except Galvanized and Silver, which contain metallic flakes and must be avoided for EV insulation work. |
Which RustSeal colors should I avoid for EV conversions? Avoid Galvanized and Silver. Both contain metallic flakes that make the coating conductive. All other RustSeal color options are formulated without metallic additives and are safe for EV insulation applications. |
How many coats of RustSeal are required for EV insulation? A minimum of 3 thin covering coats at approximately 2 mils each is recommended. This builds a thorough, continuous insulating barrier while maintaining the self-leveling, smooth finish RustSeal is known for. |
What areas of a vehicle should be coated during an EV conversion? Focus on any metal surface near high-voltage components: frames, battery boxes, motor and engine compartments, floor pans, and body panels in proximity to motors, controllers, batteries, or wiring. When in doubt, coating more surface area provides greater protection. |
Do I need to remove all rust before applying RustSeal? No. You need to remove loose, flaky rust to achieve a solid surface profile, but it is not necessary to eliminate every trace of rust. RustSeal is formulated to bond to and permanently seal remaining flash rust or corrosion. |
Can RustSeal be applied over existing paint for an EV conversion? Yes. For best results, strip the old paint first, then prep with KBS Klean and RustBlast before applying RustSeal. If full stripping is not practical, lightly scuff the existing paint with 320-grit sandpaper, clean with KBS Klean, and apply RustSeal directly over the scuffed surface. |
Ready to Prepare Your EV Conversion? RustSeal is available in multiple colors, easy to apply, and formulated to deliver a rock-hard non-conductive barrier on any metal surface. |