Global supplier of circuit protection, sensing products and industrial technology manufacturer, Littelfuse aims to protect a sustainable, connected, and safer world.
Across more than 20 countries, and with approximately 18,000 global associates, Littelfuse partner with customers to design and deliver innovative, reliable solutions.
Discussing about the chemistry of battery packs, Aishwarya had a brief talk with Navneet Vinaik, Head – Demand Creation & Sales Manager – Power Semiconductors & S. Africa, Littelfuse on the safety and reliability of its latest battery packs.
Dealing majorly in circuit protection, power control & sensing products, mention some of the key offerings of Littelfuse that differentiate Littelfuse from others.
Littelfuse has innovative solutions in all 3 domains where we serve:
- For circuit protection we have a wide range of automotive & electronic fuses to be used for pack level (high voltage/ high current), module level (high voltage/ lower current) and individual cell level protection (low voltage/ low current but we offer AEC-qualified electronics fuses designed to work in challenging automotive environment). Along with this we have a variety of over voltage protection solutions for suppressing transients and ESDs on critical interfaces like cell balancing AFE or CAN bus.
- For power control, Littelfuse offer’s industry’s best in the class figure of merit MOSFETs in the 200-300V range for 100V-200V battery packs to be used as disconnect switches. For higher voltage/ higher current ratings, we have a very wide portfolio of DC contactors going upto 1800VDC.
- Sensing solutions: Littelfuse is offering solutions for temperature sensing & high voltage leakage detection. For temperature sensing, we have NTCs for pack-level temperature measurement. For high voltage leakage detection, Littelfuse offers both Solid State Relays (SSR) & REED Relays which can be used to detect if there is any leakage path in the battery pack.
Key enabler of the Electric Vehicle (EV) sector, Battery Packs share a complex chemistry in design. Taking this in account, what role does Littelfuse products play in creating a balance to keep the battery pack stable?
Battery packs also have complex electronics which is used to measure each cell voltage and keep the voltage balanced across all the cells so that they don’t over charge & go into thermal runaway. Littelfuse offers various solutions to protect these complex electronics from transient/ESD, over temperature & over current conditions.
Also, if there is a catastrophic failure in the pack for example a capacitor which might be used on the sense line of the AFE IC can fail to short or a balancing MOSFET can fail to short, in that case we have fuses which are used on the sense lines and they safely open to eliminate the faulty cell.
Then, we offer our latest 3 terminal iTV product which is a combination of a regular over current fuse & an integrated heater element which can be turned on by the controller in case of a catastrophic event to isolate the whole battery pack from the system.
Talking about the monitoring and control of heat and charge distribution while designing a reliable battery pack, kindly tell us about the thermal management solutions?
Littelfuse offers a wide range of temperature sensors in different form factors like SMD or through hole to meet different battery pack requirements.
Designing an EV battery pack is an arduous task. Mention Littelfuse’s contribution in smoothening this work?
We help customers select the right circuit protection components and if any specific device level testing is needed, one of our various labs helps to do it to give customers real time data of how the device is performing in said conditions.
This year, the Technical Committee of the Automotive Electronics Council (AEC) has published Revision E of the AEC-Q200 standard to include fuses. Littelfuse has contributed to the development of Revision E and the framework for defining the test requirements for fuses. Revision E now provides a single standard that manufacturers can use to design and test fuses for the automotive market.
How do you define a Battery Pack as safe & reliable?
Safe and reliable battery pack should be able to take care of 3 types of threats – regular operation issues like over charge protection, over temperature protection, short circuit protection etc. Next would be proactive responses to failures which can become catastrophic like anticipating hotspots using products like NTCs and finally, in case of catastrophic failure, battery pack should be able to isolate itself quickly from the system before thermal runaway happens and our iTV product is very useful for this function.