Articles

A New Power-Cycling Strategy for Testing the Reliability of Power Electronics Modules

Dr. John Parry, Mentor Graphics Corp.

The particular power cycling strategy you choose for high-power semiconductor devices, such as power transistors, diodes, MOSFETs, and IGBTs, during reliability tests can have a significant effect on predicted lifetime results even if the tests have similar initial parameters. Also, how you set up the measurements can affect the results of the power cycling tests. Continue reading

Battery Diagnostics On-the-Fly: Removing the “Black-Box” Stigma by Making Performance Transparent

Isidor Buchmann, CEO & Founder, Cadex Electronics, Inc.     

Battery users imagine a battery pack being an energy storage device that resembles a fuel tank dispensing liquid fuel. For simplicity reasons, a battery can indeed be perceived as a vessel storing electrical energy; however, measuring energy flowing into an electrochemical device and then drawing it out again is far more complex than handling liquid fuel. While a hydraulic fuel gauge measures liquids moving in and out of a tank of known size, a battery fuel gauge reads units of current. Battery size is specified in ampere hours (Ah), and what makes estimating battery state-of-charge (SoC) and state-of-health (SoH) so challenging is an unsteady state; a battery loses capacity with each charge and leaks energy in the form of self-discharge. Continue reading

How to Measure Battery Internal Resistance Using the Current Interrupt Method

James Niemann, Analog Design Engineer, Tektronix

One of the demonstrations we often set up at battery conferences is to use a source measure unit (SMU) to measure the internal resistance of an energy storage device such as a battery or a fuel cell. In such demonstrations, the SMU changes the load current from the battery operating current or the polarizing current to the open circuit potential and simultaneously measures the change in cell voltage. In this “current interrupt method,” the battery’s internal resistance is equal to the change in voltage divided by the change in current. Continue reading

Q&A with Inventus Power CEO Pat Trippel

Battery Power’s Senior Editor, Shannon Given, had the opportunity to interview Pat Trippel, the recently announced CEO of Inventus Power. Inventus Power is the is the largest vertically integrated power systems manufacturer in the US and produces custom battery solutions for medical, military, commercial and consumer markets in nine countries across the globe. Continue reading

Improve Tab to Terminal Connections in Battery Pack Manufacturing

Geoff Shannon, Amada Miyachi America, Inc.

Battery packs have become an integral part of everyday life, powering a growing range of portable electronic devices, cordless power tools, energy storage, and hybrid and electric vehicles. Tab to terminal connection welding is one of the key battery pack manufacturing applications. Manufacturers need equipment, systems, and automated lines that meet quality and production requirements for these products. Both resistance and laser products are well suited to integration into production lines that may be either standalone or automated operation. To maintain the required throughput that offers high quality and yields, users must have a clear understanding of which process is best for the particular battery pack size, tab and terminal material, type, and thickness. In addition, the selected process and integration solution should include process monitoring, process data management, and weld quality assessment. Continue reading

Sorting Busbar Choices for Electric Vehicle Power Distribution

Dominik Pawlik, Technical Marketing Manager
Rogers Corp., Power Electronics Solutions (PES)

Interest in electric vehicles (EVs) and hybrid electric vehicles (HEVs) is growing steadily as battery technologies improve and the driving range of such vehicles increases. Perhaps as important, EVs/HEVs offer a “green” alternative to traditional vehicles powered by internal-combustion gasoline engines. Continue reading

Protecting Lithium Batteries and Battery Packs from Runaway Thermal Events

BS&B Safety Systems

The market for lithium batteries and battery packs is booming.  With extensive applications in automotive, IT, aerospace, consumer electronics and a myriad of industrial sectors, the usage of rechargeable lithium batteries is growing throughout the world.  The market for lithium-ion batteries alone is expected to exceed $30 billion in the next few years. Continue reading