Battery-assisted Electric Vehicle Charging: Data Driven Performance Analysis

TL;DR

This study evaluates how battery-assisted EV charging can replace high-speed chargers at large scales, showing near-parity performance in domestic and non-domestic settings through data-driven simulations.

Contribution

It introduces a discrete-event EV charge model and assesses battery-assisted charging performance across extensive real-world data, filling a gap in large-scale impact analysis.

Findings

Domestic battery-assisted charging achieves 98% parity with high-speed chargers.

Non-domestic settings reach up to 99% parity with 10 batteries and higher grid capacity.

Battery-assisted charging significantly reduces reliance on high-speed chargers at scale.

Abstract

As the number of electric vehicles rapidly increases, their peak demand on the grid becomes one of the major challenges. A battery-assisted charging concept has emerged recently, which allows to accumulate energy during off-peak hours and in-between charging sessions to boost-charge the vehicle at a higher rate than available from the grid. While prior research focused on the design and implementation aspects of battery-assisted charging, its impact at large geographical scales remains largely unexplored. In this paper we analyse to which extent the battery-assisted charging can replace high-speed chargers using a dataset of over 3 million EV charging sessions in both domestic and public setting in the UK. We first develop a discrete-event EV charge model that takes into account battery capacity, grid supply capacity and power output among other parameters. We then run simulations to evaluate the battery-assisted charging performance in terms of delivered energy, charging time and parity with conventional high-speed chargers. The results indicate that in domestic settings battery-assisted charging provides 98% performance parity of high-speed chargers from a standard 3 kW grid connection with a single battery pack. For non-domestic settings, the battery-assisted chargers can provide 92% and 99% performance parity of high-speed chargers with 10 battery packs using 3kW and 7kW grid supply respectively.