By Jim MacGregor
When COVID-19 cases spiked last March, most people figured that we were looking at a limited shutdown—perhaps a few months. This happened just as sound companies and rental houses were preparing for the summer concert season. The global lockdown was extremely trying for everyone, and the pro audio community felt its share of the impact in 2020.
The past year has been a pretty rough time for the music industry, especially in live events. No tours, no venues, no festivals—for a full year. Now, with vaccines being distributed, live events are being tentatively planned, venues are slowly being reopened, and equipment in storage is being readied for normal use.
For most equipment, standard downtime procedures apply: Pull out that gear, dust it off, set it up, and make sure it’s sounding good and ready for action. Check your cables, lubricate wheels and hinges, tighten screws and bolts.
But while most sound companies and rental houses have solid procedures for off-season storage and reboot, one year is a long time, especially for batteries. Most of today’s wireless systems—microphones, in-ears, and intercoms—are designed for constant usage via lithium ion rechargeable batteries. The problem? No company plans for its gear to spend a full year offline.
Here’s a key fact: Even when not plugged in or powered up, all battery cells remain electrically active. That means a small, steady loss of power over time that, potentially, can affect performance. While in theory, everything should be fine, you’ll want to confirm that everything is working properly before your wireless system is back in service. So, just as you will need fresh frequency scans for your wireless systems, it’s equally important to make sure their batteries are performing properly.
Many a wireless system today features advanced lithium ion rechargeable batteries. These are marvels of engineering, highly resistant to memory effects and degradation. Assuming they were stored at room temperature range, it’s unlikely there will be any issue. Still, storing batteries for a full year was never part of the plan. Fortunately, the engineers at Shure have been studying the situation.
If your battery charger offers a Storage Mode, use it! This feature charges the batteries to a slightly depleted state, optimal for long-term storage. Several Shure chargers offer this feature. For example, the AXT900 charger can put the batteries in storage mode. This puts the voltage of the battery at a mid-range point (3.8 volts), which is best for the battery.
Also, keep the battery from getting too hot or too cold. Lithium ion batteries can lose health when stored in cold or hot areas. For best performance, store the batteries in normal room temperatures.
If you haven’t used your rechargeable batteries in a while, don’t wait; do the following now: Put your lithium ion batteries through several power cycles—at least two—before being returned to routine service. This serves to physically demonstrate the run time while simultaneously stabilizing the electrochemical properties of the batteries. Please review your owner’s manual and documentation and follow all other safety recommendations for handling lithium ion batteries. If your battery fails to charge after the power cycles, contact the manufacturer for further guidelines.
We’re all excited at the prospect of the live events industry working again. At the same time, we urge everyone to be patient, stay safe, and follow appropriate protocols.
Jim MacGregor is senior manager, Global Pro Audio Marketing at Shure.
Shure • www.shure.com