A customer wrote in the other day, to thank us for the seamless delivery of a valve-regulated battery for their mobility device. Now it is in position and working smoothly, they asked, may I ask you how your VRLA lead-acid batteries work so reliably that I never have to worry. We wrote them an email that they thanked us for gratefully, and we decided to re-post it here.
What Goes on Inside Valve Regulated Lead Batteries
A VRLA battery has a series of separated lead plates in pairs inside. A silica gel of diluted sulfuric acid surrounds them, protecting them from vibration and promoting a long, successful life. VRLA lead-acid batteries are sealed in their cases, so no hydrogen gas escapes during use, and they never need topping up during their lifetime.
A chemical reaction occurs between the lead plates in pairs, and the sulfuric-acid gel, each time you use the battery. This causes the sulfate in the gel to escape, and bond with the lead until it reaches a critical point. At this stage the battery is what we informally call ‘flat’, because it is no longer able to deliver a decent charge.
However, you can put the sulfate back into the gel, by recharging the battery using an external electricity source. Most of the sulfate leaves the lead plates, but a very small amount remains behind. Lead battery scientists are trying to resolve this issue. But for now, this is why our batteries will not keep going forever.
VRLA Batteries Do More Than Powering Mobility Devices
The internal stability of VRLA lead-acid batteries means they can work at any angle that suits the application. That, and their long life between charges means they perform well in a variety of situations.
We haven’t tried these ideas ourselves, but Wikipedia assures that VRLA batteries have found a home in nuclear submarines, and sailplanes. We think we’ll stick to mobility devices, back-up systems, golf carts, and other devices on solid ground, for now.
More Information
Electric Submarine Power Beneath the Ocean
