Ten Best Ways to Use Batteries
December 6, 2014
Batteries are the lifeblood of an RTLS. Unless you’re using passive tags (that have no battery), without batteries, the whole system shuts down.
The key types of batteries that you typically find in RTLS tags (and optionally, location sensors) are: Leclanché, alkaline, nickel-metal hydride (NiMH), lithium, silver oxide, zinc air, and nickel cadmium (NiCd). Some RTLS use primary (non-rechargeable) batteries, and others use secondary (rechargeable) batteries. This chapter describes ten important points to consider when using batteries for RTLS.
Maximizing Battery Life
Batteries lose life because of usage — even when not in use. As the cell ages, the composition and structure of the materials changes, and the result is that the cell capacity deteriorates. You can’t do much about usage or aging; however, battery life also depends upon environmental conditions:
✓ Operating temperature: Batteries have a limited temperature range over which they work. Attempting to use the battery outside these limits usually results in a permanent degradation in performance or a complete failure.
Keep the operating temperature limits in mind when selecting your RTLS and batteries.
✓ Operating pressure: Excessive pressure can cause mechanical failures, such as short circuits between parts, interruptions in the current path, distortion or swelling of the cell case, or in the worst case, actual rupture of the cell casing, within a battery’s cells.
Keep the operating pressure limits to which the tags will be subjected to in mind when selecting your RTLS.
Understanding That Not All Batteries Are the Same
In real life, note that all batteries (even from the same manufacturer and the same model) don’t deliver their rated capacity. This is due to the manufacturing variations, and these manufacturing variations happen in spite of the fact that manufacturing processes are highly automated and mechanized. The main reason behind this is the spread in the materials’ properties used in batteries.
In fact, this manufacturing tolerance spread is one of the key factors behind the wide disparity in the performance of similar batteries from different manufacturers.
Disposing of Used Batteries
Unlike single-use batteries, rechargeable batteries continue to make use of potentially toxic heavy metals, such as cadmium, nickel, and lead, which can threaten the environment if not properly discarded. Check with your local government health, solid waste, or recycling department before you consider their disposal.
Rechargeable batteries aren’t the only type that can be recycled. Many recycling facilities collect and recycle disposable batteries also.
Under no circumstances should batteries be incinerated because they can explode. If your skin is exposed to an electrolyte, flush with water immediately. If eye exposure occurs, flush with water for 15 minutes and consult a physician immediately.