Your laptop's battery gauge says you have an hour of computing time left, but don't count on it. The older a lithium-ion laptop battery, the less energy it can typically store -- a variation that can throw off the accuracy of conventional battery gauges by more than 50 percent. This winter, Texas Instruments plans to introduce an inexpensive "gas gauge" chip that not only takes into account a battery's original capacity but also measures its impedance -- the resistance to electrical current caused by age, frequent use, and other factors. Built into the chip are mathematical models of lithium-ion chemistry that use impedance measurements to calculate how much a battery has degraded and adjust predictions of remaining charge accordingly.
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Manufacturing in the United States is in trouble. That's bad news not just for the country's economy but for the future of innovation.
This document is part of the “How-To Guide for Most Common Measurements” centralized resource portal. This tutorial provides a detailed guide for measurement and device considerations to take temperature measurements using thermocouples. Get an introduction to thermocouples, which are inexpensive sensing devices widely used with PC-based data acquisition systems. Also review some specific thermocouple examples and learn how thermocouples work and ways to integrate them into a data acquisition measurement system.
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