The increasing deployment of battery electric vehicles (BEVs), particularly in commercial and heavy-duty applications, is driving demand for higher DC fast-charging power while placing growing pressure on battery lifetime and local grid capacity. In today’s multi-battery-pack vehicles, a common practical solution is the use of multi-step or multi-constant CC-CV charging, where charging current is reduced in stages to accommodate pack-to-pack differences in state of charge, state of health, and ageing behavior. While effective from a safety standpoint, this approach often leads to conservative charging profiles, longer charging times, and inefficient use of available grid power, especially at higher charging rates.
This paper presents an onboard pulse-charging concept for electric powertrains that addresses these limitations through a combination of vehicle-side power electronics and an adaptive control strategy referred to as Stochastic Gradient Pulse Adaptation (SGPA). Instead of relying on predefined current steps or a fixed CV phase, pulsed DC power is generated onboard using a “chop-and-serve” architecture. A switched-mode power stage at each battery junction box—scalable to one converter per battery pack—converts the constant DC output of the charging station into controlled current pulses. This allows independent current control for each battery pack, internal mitigation of pack heterogeneity, and continued use of existing CCS and MCS infrastructure without increasing inlet current or conductor power density.
The SGPA strategy adapts pulse amplitude and duty cycle in real time based on battery-internal signals such as temperature, terminal voltage, internal resistance, and state of charge, supported by the curvature of the voltage–capacity relationship. Charging aggressiveness is increased when conditions are favorable and reduced only when indicators of thermal or electrochemical stress become significant, removing the need for conservative multi-CCCV derating.
Simulation-based proof-of-concept results for a heavy-duty battery system indicate charging-time reductions of up to 20–30 % compared to multi-CCCV charging, while improving current distribution in heterogeneous multi-pack powertrain configurations. The proposed approach offers a practical and scalable pathway toward faster, battery-aware, and grid-compatible DC fast charging for heavy-duty electric powertrains.