Kinaguiden is a precision aluminium die casting company based in Stockholm, Sweden, supplying components for the automotive, electronics, and renewable energy sectors including EV applications.
The transition to electric vehicles is one of the most significant structural shifts in manufacturing demand in decades. Aluminium die casting sits at the centre of it — EV drivetrains, battery systems, and charging infrastructure all rely heavily on high-pressure die cast aluminium components. This guide covers the key applications, the specific design and alloy considerations for EV parts, and why HPDC is the right process for most of them.
Why Aluminium Die Casting Is Central to EV Manufacturing
Electric vehicles have fundamentally different structural and thermal requirements compared to internal combustion engine vehicles. The battery pack — which is both the heaviest and most thermally sensitive component — drives a set of requirements that aluminium die casting is uniquely positioned to meet:
- Weight reduction: Every kilogram saved in structure directly extends driving range. Aluminium at 2.7 g/cm³ is roughly one-third the density of steel, and die casting allows complex geometry to be achieved in a single part that would require multiple welded steel components.
- Thermal management: Batteries, motors and power electronics generate heat that must be managed precisely. Die cast aluminium has good thermal conductivity (96–160 W/m·K depending on alloy), and integrated cooling channels can be cast directly into housing walls.
- EMI shielding: Inverters, onboard chargers and control electronics require electromagnetic shielding. Die cast aluminium enclosures provide effective EMI containment.
- High-volume production: HPDC cycle times of seconds per part make it suitable for the production volumes required by automotive supply chains.
Key EV Applications for Aluminium Die Casting
Battery Module Housings and Enclosures
Battery enclosures must be structurally rigid, electrically insulating (relative to the cells), thermally conductive to the cooling system, and in many designs pressure- or liquid-tight. HPDC aluminium is used for both individual module housings and the structural frame components of full battery packs.
Design considerations include: integrated cooling channels or fins, sealing grooves for O-rings or gaskets, boss features for mechanical cell retention, and cable routing slots. A360 alloy is often preferred for these applications due to its superior corrosion resistance and ductility — important for a housing exposed to coolant and potentially corrosive battery chemistry.
Electric Motor Housings
The motor housing must dissipate heat from both the stator windings and the rotor bearings while maintaining precise bore geometry for bearing seats. HPDC aluminium allows cooling fins and oil or water jacket channels to be integrated directly into the casting, reducing the number of components and eliminating the thermal resistance of a bolted joint.
A380 is commonly used for motor housings due to its high thermal conductivity and good strength. Where the housing requires significant CNC machining of the bearing bores, AlSi9Cu3 (EN AC-46000) is preferred for its excellent machinability.
Inverter and Power Electronics Enclosures
The inverter converts DC from the battery to AC for the motor and handles peak currents of hundreds of amperes. The enclosure must provide EMI shielding, thermal management (the IGBTs and MOSFETs it contains generate significant heat), and structural protection for the PCB assembly.
HPDC allows thin-wall enclosures with integrated heat sink fins, mounting bosses, and connector apertures to be produced in a single shot. Wall thickness of 1.5–2.5 mm is typical. ADC12 or A380 are standard alloy choices.
EV Charging Infrastructure Components
Charging station housings, cable management components, and connector assemblies are increasingly produced in aluminium die casting. These parts must withstand outdoor conditions including moisture, UV, and temperature cycling. A360 with a powder coat or hard anodize finish is the standard specification for outdoor EV charging hardware.
Structural and Suspension Components
Large-format structural die castings — including subframe nodes, battery tray structures, and suspension knuckles — are an emerging area of HPDC. These "mega-castings" consolidate multiple previously stamped and welded steel parts into a single large die cast component. This approach requires very large die casting machines (typically 6,000–9,000 tonnes clamping force) and specialised low-porosity casting techniques for parts that must meet crash performance requirements.
Alloy Selection Summary for EV Applications
| Application | Recommended Alloy | Key Reason |
|---|---|---|
| Battery enclosure | A360 | Corrosion resistance, ductility |
| Motor housing | A380 or AlSi9Cu3 | Thermal conductivity / machinability |
| Inverter housing | ADC12 or A380 | Castability, thin walls |
| Outdoor EV charger | A360 + powder coat | Weathering resistance |
| Structural nodes | AlSi10MnMg (Silafont) | High ductility, crash energy absorption |
Design Considerations Specific to EV Parts
Pressure Tightness and Impregnation
Battery cooling circuits and motor water jackets must be liquid-tight. Standard HPDC parts contain micro-porosity from gas entrapment during injection that can cause leaks under pressure. For pressure-tight applications, specify vacuum-assisted die casting or post-cast vacuum impregnation (resin sealing of porosity). Both approaches are well-established and cost-effective.
Integrated Cooling Channel Design
Cooling channels can be formed in die casting using soluble cores (lost-core casting) or by casting a thin-wall channel that is capped by a separate machined cover plate. The latter approach is simpler and more common. Channel wall thickness should be minimum 2.0 mm to ensure fill and structural integrity.
EMI Gasket Groove Design
For EMI-shielded enclosures, the mating faces must accommodate a conductive gasket. This requires a machined face flatness of better than 0.1 mm and a groove profile sized for the gasket. Design the groove to be accessible from the parting direction to avoid side actions.
Kinaguiden supplies aluminium die cast components for EV charging infrastructure, motor housings, and electronic enclosures. We advise on alloy selection, pressure-tightness requirements, and surface finish for EV applications. Contact us with your drawing or project description for a detailed quote.