Audi on high voltage battery development
Mr. Thömmes, Head of Development Software Functions and Electronics for HV-Batteries at AUDI AG, will talk about the biggest trends and issues in fast battery charging and necessary improvements in the BMS in order to handle energy demand efficiently.
What do you think will be the future trends in battery electronics?
In the future we will see more intelligent solutions based on electronics and semiconductor devices and less electromechanical parts as relays or conventional fuses. Wireless communication could be ready almost 2025 for internal battery communication. We will see a modularization of electronics and a standardization of functions e.g. current, voltage and isolation measurement.
Today, what are the biggest issues fast battery charging is facing?
The biggest issue is the charging infrastructure. We need much more charging stations in the future to enable e-mobility for everyone. This means especially charging stations for urban regions where many people don’t have their own charger at home, but have to park on public areas. There we need a sufficient amount of possibilities to recharge the cars. Additionally there is a need for a unified payment system, so you can charge your car at any charging station. Also we need more fast chargers near high ways, in order to reduce waiting time for long distance travelers.
In your opinion, are solid-state batteries the way to go for fast charging? Why/ why not?
We definitely need a new technology from 2025 on and that could be solid-state batteries at the moment. They promise many advantages compared to the actual technology for fast charging, but also have some disadvantages such as the limited ionic and electrical conductivity of the electrode materials or the necessary manufacturing methods for large scale batteries. When those disadvantages have overcome they are a very interesting option for facing the challenges in fast charging.
What improvements are needed in the BMS in order to handle energy demand efficiently?
We need a new electronic architecture and intelligent algorithms especially for the thermal management of battery systems. In the future we will see batteries with higher voltages to reduce currents and weight of the high voltage system of BEVs. With reduced currents we will reduce losses especially in power electronics and the weight of the cable harness due to reduced cross sections. Also new technologies as Siliciumcarbid (SiC) will help us to be more efficient. For example a 800V system as Audi showed it in the Audi Aicon will reduces also charging time as one important enabler for BEVs.
How far is the market to achieve a fully electrified vehicle? Will it be a reality by 2020?
Yes definitely. We will see the first electrified vehicles with sufficient range for our customers end of 2018 with the introduction of our Audi e-tron. I had the possibility for a test drive with the e-tron – it’s amazing. Unitl 2020 there will be three fully electric Audi models in the market.
Adding new automated functions in the car, going through full electrification of the powertrain, or using 48V technology for hybrids have added some extra stress factors for car makers to have an optimized energy distribution throughout the vehicle. Are current battery management system solutions able to fully manage this? Or should we expect more upgrades and news in the coming years?
Intelligent software functions will increase rapidly and therefore we need more computing power in our cars. New electronic architectures will have high performance computers and there will be a direct link to backend computers outside the car. Over the air update will be the standard in the future. The biggest challenge from my point of few is how we will handle the constantly increasing complexity of software