New lithium polymer battery cells offer thermal protection for ultra-thin portable electronics

September 25, 2012 // By Paul Buckley
TE Circuit Protection, a business unit of TE Connectivity Ltd., has introduced the MHP-TA series of ultra-low-profile (L: 5.8 mm x W: 3.75 mm x H: 1.15 mm) resettable thermal cut-off (TCO) devices for lithium battery protection.

The MHP-TA series of devices features a 9 Vdc rating, two product categories with different levels of current-carrying capacity, and multiple cut-off temperature ratings.

The MHP-TA series is an extension of TE Circuit Protection’s innovative MHP (Metal Hybrid PPTC) technology, which connects a bimetal protector in parallel with a PPTC (polymeric positive temperature coefficient) device. The initial MHP product offerings, the MHP30-36 and MHP-SA series, targeted higher-current (above 30 Vdc, 30 A) Li-ion battery pack applications used in portable power tools and energy storage systems.

The new MHP-TA series is intended for applications with lower voltage and current ratings. As a result, TE Circuit Protection was able to downsize the MHP product to offer an ultra-compact device that meets the space requirements of the growing LiP market. In battery cell designs, the MHP-TA series helps provide resettable overtemperature protection, while utilizing the PPTC to act as a heater and to keep the bimetal latched until the fault is removed.

The MHP-TA series comprises nine devices with two levels of current carrying capacity:  low-current MHP-TA6-9 products with an approximately 6 A hold current @25°C, and high-current MHP-TA15-9 products providing a hold current of approximately 15 A. The low-current MHP-TA6-9 devices are available in four different current ratings (72°C, 77°C, 82°C, 85°C) and the high-current MHP-TA15 devices in five ratings (72°C, 77°C, 82°C, 85°C, 90°C).

More information about the MHP-TA series at www.circuitprotection.com