Power antifuse device to bypass or turn-off battery cells in safety-critical and fail-operational systems

This paper presents a new power electronic device, named power antifuse, providing an irreversible bypassing function for the current after having been ignited by an external electrical signal. The antifuse is a scalable power electronic device of 1 cm² of active area. A pristine antifuse device provides an electric resistance of more than 100 mega-ohms between the terminals. After having been activated, the same antifuse device becomes a bidirectional bypass element offering less than 20 micro-ohms of resistance to the electric current. The activation time corresponding to the delay between the reception of the electrical trigger signal and the full conduction of the antifuse is less than 10 ms even at environment temperatures below -40°C. This paper shows how the integration of antifuse devices in battery cells can be used to bypass and turn-off lithium-ion battery cells thus improving the safety and availability of battery systems used in transport applications like aircraft, railways, ship and road vehicles. The characteristics of the proposed antifuse device make it also an ideal power electronic device for bypassing faulty series connected sub-systems used in high-availability applications or fail-operational redundant systems.

I. Introduction

Nowadays, battery systems based on series connections of lithium-ion battery cells are widely used in a vast variety of mobile and stationary applications [1] [2]. Since lithium based batteries provide a high energy density, they are potentially dangerous when they release their energy in an uncontrolled way. The hazards can be of several types, for example chemical, mechanical, electrical or thermal. A faulty battery cell principally generates two main threats: •

The threat coming from the faulty battery cell (e.g., thermal runaway, electrolyte or gas leakage, explosion, fire)

•

The threat of making the system unusable or worse, destroying it and hurting persons