EV battery tapes, by the job inside the pack

Nickel-strip wrapping and interconnect insulation

Cells are joined by nickel strips, and every one of those strips has to be isolated from the casing and from its neighbours. This is the job Mr.Bond® Polyimide Tape is made for: the silicone adhesive secures and shields the nickel strips during demanding tasks, while the polyimide film acts as the dielectric barrier. It carries a Class 180°C thermal rating and is supplied in flame-retardant (FR) grade with outstanding dielectric strength, and because the film is thin and flexible it insulates without increasing the overall weight of the pack.

Where the wrapping job is a coil or a conductor rather than a flat strip, Mr.Bond® Black Cotton Tape takes over. It is made from 100% fine insulated cotton substrate backed with a strong rubber-based adhesive and is used for conductor wrapping, connection wrapping and interlayer coil insulation. It is available in white and black, and sizes and thicknesses can be customised.

Cell-to-casing thermal management

Cells generate heat as they charge and discharge, and that heat has to reach the structure to leave the pack. LJIPL Mr.Bond® Thermal Pads sit between the battery cells and the casing and give the heat that path: good thermal conductivity with low thermal resistance, while remaining an excellent insulation material electrically. They are UL 94V0 approved and can be supplied with thermal conductivity from 1 W/m·K to 8 W/m·K as per your specification. Because the pad is compressible it allows for the expansion and contraction of cells through the charge cycle and aids in securing the cells in position when vibrations occur.

Prateek® Nitrile Foam Tape does the same class of work in tape form: it is used as a thermal interface material, helping transfer heat away from the battery cells and keeping thermal connections consistent within the pack. If you are still deciding what to specify, the thermal interface materials page explains what to measure and send before you enquire, and what W/m·K means when specifying a thermal pad explains why the gap and the contact pressure matter as much as the conductivity figure you have been handed.

EMI / EMC shielding and grounding

Power electronics in an electric vehicle switch hard and fast, and the interference they radiate has to be contained rather than allowed to upset neighbouring circuits. Copper Foil Tape is coated with an electrically conductive, pressure-sensitive acrylic adhesive, which is the detail that matters: with a conductive glue line, overlapping strips of foil are joined electrically, so a wrapped harness or a taped enclosure seam behaves as one continuous shield instead of a row of separate patches. It is supplied at 65 to 70 micron, is specially designed for EV application, passes the 2-point test method and bears a temperature range of T2. Why that adhesive detail decides whether a shield works at all, and what to specify for a grounding connection as distinct from a barrier, is set out in copper foil tape for EMI shielding and grounding.

Busbar and general electrical insulation

Away from the interconnects, most of the electrical insulation work in a pack is harness runs, busbar covering and casing finishing. PVC Insulation Tape is the workhorse here: it provides dielectric protection for EV wiring, conductor wrapping and battery pack assembly, and adds moisture, weather and abrasion resistance. Multiple widths and colours are available on request, which is what makes colour-coded harness work practical.

Many packs use both tapes together, polyimide at the hot, tightly packed interconnects and PVC on the runs and casing work around them. Where the insulation has to survive sustained heat outside the pack, the PTFE-coated fibreglass heat sealing tape carries the same Class H (180°C) rating with high dielectric strength and low, non-tracking electrical losses. The full comparison of insulation carriers, including the polyester (PET) tapes used in transformers, capacitors and LED TVs, is in polyimide, PVC or polyester.

Pack assembly, sealing and bundling

Once the electrical work is done the pack still has to be held together and closed up. LKJ® EVA Double-Sided Foam Tape gives stable adhesion when fixing components within the battery assembly, circuit boards, battery cells, displays and other critical parts. Acrylic Foam Tape handles gasketing: it helps preserve a water-resistant seal between the casing and the rubber gasket, fills gaps between rigid components and reduces the need for fasteners, with a VHB variant also available.

LKJ® Cross Filament Tape is the bundling tape, a film backing with rubber adhesive reinforced by woven glass fibre for high breaking strength, used for packing EV battery modules. Finally, Black Binding Sealing Tape covers the waterproof sealant within the MS case and tidies the finished appearance of the pack.

The LJIPL catalogue lists these together on its final page as “tapes and other products for EV battery industry”, alongside copper foil tapes, nitrile foam tape and thermal conductive tapes.

Pack-level products compared

What to send us with your enquiry

Every tape here is made to order, so the quote follows the drawing rather than a stock list. Custom slitting runs from 12 mm to 1200 mm and sizes and thicknesses can be customised as per requirements, so the useful things to send are the width and roll length you need, the surfaces the tape has to hold on, the temperature the assembly reaches, the gap a pad has to fill, and any flame rating or thermal conductivity your design calls for. Samples are available on request. Send a drawing or a description to our engineering team and the grade will be specified against it. If a flammability class is written into your specification, our guide to what UL 94 V-0 means on a tape explains what the classification covers and which products in this range carry it.