A battery is a device consisting of one or more electrochemical cells that convert stored chemical energy into electrical energy. Batteries are available in
numerous sizes and types though all rely on the ability to maintain a charge in order to function properly. Battery testers are the class of instruments designed
to assess the condition—the charge, impedance, ripple current, or other measurement—of batteries to ensure they are working as required. Just as batteries have
a very wide range of sizes and uses, so do battery testers. They range from inexpensive units designed to make sure small batteries have enough charge to power
up a camera, to much more sophisticated devices for testing long strings of powerful batteries in industrial settings.
Despite the range of technology and uses, there are two basic types of batteries:
Primary cell batteries transform chemical energy to electrical energy. When the reactants inside the battery are exhausted, the battery is dead and
energy cannot be effectively restored rendering the batteries disposable. Primary cell batteries are commonly used with portable electronic devices that have low
current drain and are not used continuously. Common types of disposable batteries include zinc–carbon batteries and alkaline batteries.
Secondary cell batteries are known as rechargeable batteries since supplying an electrical charge to the battery reverses the chemical reactions
that occurred between the battery’s reactants allowing them to be charged over and over again. Secondary cell batteries can deliver high peak currents. Common types
include lead acid, nickel–cadmium (NiCd), nickel–zinc (NiZn), nickel metal hydride (NiMH), and lithium-ion (Li-ion). Over time, the reactants inside secondary cell
batteries dissipate and degrade diminishing their capacity of the battery to recharge and limiting its life-cycle.
Testing primary cell batteries is simple. An electrical tester, often a multimeter, is touched to the positive and negative terminals. The potential voltage of
the battery is compared to the test results and the amount of charge remaining can be figured. Many battery testers utilize a color-coded scale which automatically
“passes or fails” batteries.
The characteristics of secondary cell batteries varies over load cycle, charge cycle, and lifetime due to factors including internal chemistry, current drain, and
temperature making them a bit more complicated to test and requiring more advanced equipment. Sophisticated battery testers can assess a range of range of factors
to determine the overall health of batteries.
These testers work by applying a test signal across the battery string while on-line and then calculating impedance based on simultaneous measurements of current
and resulting voltage drop of each cell/jar. They also measure DC voltage and interconnection (strap) resistance to help determine the overall condition of the
entire battery string’s electrical path from terminal plate to terminal plate. Unlike load cycle testing that involves substantial downtime and repeated discharges,
using these testers require no battery discharge, nor do they stress the battery in any way compared to other techniques. With a short test time and intercell
connector, one person can quickly and easily measure internal cell impedance, DC terminal voltage and intercell connection resistance without taking the battery
system off line.
Applications for Battery Testers:
- Electrical power generation plants
- Utility, railroad, and industrial substations
- Telecommunications facilities: CO, Wireline, Wireless, MTSO
- UPS systems
- Railroad signaling and communication substations
- Aircraft power supplies
- Marine, military
If you have any questions regarding battery testers please don't hesitate to speak with one of our engineers by e-mailing us at sales@instrumart.com or calling 1-800-884-4967.
