South Korea’s INFAC Corporation has introduced a new 800V battery pack design block for electric vehicles that integrates an 800V-to-48V high-power isolated and regulated DC-DC converter. The new design will enhance range, power efficiency and vehicle performance by reducing the need for high-voltage cables and connectors.
Instead of having the DC-DC conversion stage as a distributed, separated subsystem, INFAC’s approach is to convert the battery’s high voltage from 800V to 48V near the battery source so that it can be distributed as a 48V SELV supply across the vehicle. This simplified approach allows lower voltage, versatile, more modular 48V zonal architectures for different EV platforms without replacing battery cells or impacting range.
Re-imagining what is possible between battery packs and DC-DC converters
INFAC recognized that traditional approaches to power delivery were misaligned with industry goals for weight reduction, cost optimization and design simplicity.
High voltage DC-DC converters are typically mounted outside the high-voltage (800V or 400V) battery assembly system (BAS), requiring additional safety and thermal management systems. The EV motor and inverter systems demand hundreds of kilowatts of power and require high-voltage wiring harnesses, brackets and enclosures. Other powertrain subsystems and body and chassis electronics require 3.5 – 12kW, and can be easily powered from a 48V SELV zonal power distribution network.
Physically separating the high-voltage source and DC-DC conversion power system unnecessarily duplicates power distribution and management systems, which wastes space, weight and cost and doubles the liquid cooling systems required.
The innovation: Moving DC-DC conversion inside the battery pack
INFAC’s key insight was that the battery pack already incorporates a robust liquid cooling system for managing thermal loads. By integrating the high voltage DC-DC converter inside the battery, and leveraging the existing infrastructure INFAC eliminated the separate cooling system which traditionally resides outside the battery pack for the DC-DC converter. This departs from conventional “silver-box” design approaches by positioning the battery pack as a central, intelligent power hub rather than a passive energy source.
The change was made using Vicor high-density BCM6135 DC-DC converters and PRM3735 regulators, which provide HV-to-48V conversion and regulation and enable a high-power, fully isolated and regulated bus for the zonal architecture.
Previously, housing the DC-DC conversion function inside the battery pack was impractical as size constraints forced designers to grapple with power management issues, electrical isolation, safety requirements and power module packaging robustness.
Benefits of battery-integrated DC-DC conversion
By co-locating the DC-DC converter within the battery pack, INFAC realized a series of benefits that increased performance at the system level:
- By leveraging the battery’s liquid cooling network, the power module eliminates redundant coolant loops and reduces thermal interfaces.
- High-voltage cable length and thickness are significantly reduced, simplifying high-voltage harness routing and layout.
- Fewer brackets, enclosures and cooling components reduce BOM costs, and weight.
- Minimizing connections and cooling paths reduces leak points and electrical failure risks.
- Fewer external interfaces mean faster, more consistent manufacturing processes.
Vicor high-density, modular power architecture provides the efficiency, scalability and compact form factor required to make battery-integrated 48V distribution practical at scale. In doing so, it positions the battery pack as the central power management and distribution hub for next-generation electric vehicles and enables INFAC to align its EV battery pack designs with the industry’s broader transition toward 48V zonal power architectures.
