Thermal Protection for Li Batteries in Ultra-Thin Applications

Battery applications designers are tasked with meeting increasingly stringent safety standards for ultra-thin notebooks and other portable consumer electronics powered by high-capacity lithium polymer and prismatic cells. In response, TE Connectivity's business unit, TE Circuit Protection, introduces the new MHP-TAM series. The MHP-TAM device features an ultra-low-profile (L: 5.8mm x W: 3.85mm x H: 1.15mm max.) package and a high (9Vdc) rating. The devices in the series offer a choice of two different levels of current-carrying capacity and multiple cut-off temperature ratings. The device provides a space-efficient thermal cutoff (TCO) solution that helps designers meet the demanding peak-current requirements of consumer products.

Utilizing innovative MHP (metal hybrid PPTC) technology, the MHP-TAM device combines a bimetal protector in parallel with a PPTC (polymeric positive temperature coefficient) device. In battery applications, the MHP-TAM device helps provide resettable over-temperature protection to shut down the battery when a fault is detected. The device rests when the fault is removed. The devices in the MHP-TAM series feature different open temperatures, ranging from 72 to 90 degrees C (typical), which are appropriate for the battery market. They also offer two levels of hold currents: low-current (approximately 6A at 25 degrees C) and high-current (approximately 15A at 25 degrees C).

“To help meet the thermal protection requirements of lithium polymer battery applications, our new MHP-TAM devices have been tested to withstand the harshest humidity test conditions in the battery industry. High reliability is important since OEMs are tightening their component reliability requirements for lithium polymer battery packs used in consumer applications,” said Amy Chu, Product Manager of TE Circuit Protection. “Over the last 30 years, TE Circuit Protection has been a front-runner in utilizing PPTC technology to introduce high-reliability solutions for battery protection. The addition of the new MHP-TAM series offers designers even more choices when selecting the best protection device for today’s consumer electronics.”