The Amateur Amateur: Assaulting the Battery

By Gary Hoffman, KB0H
Contributing Editor
January 14, 2002

I wrote this column to share with you what I've learned about batteries. Some of what I'm about to say is going to make me look pretty stupid.

Some of you amateur-amateurs just cannot relate to my stories. You do not have a mobile radio mounted in your car. You do not climb onto the roof of your house to mess with antennas. Above all, you never, ever plan to learn Morse code. This column is for you (and I apologize for its being a two parter). You'll be able to relate to this one, guys. I'm going to talk about the nickel-cadmium (NiCad) batteries that you may have in your hand-held radio (many manufacturers now are turning to nickel metal hydride (NiMH) or lithium ion batteries--Ed).

As did many of you, my wife and I got our Technician licenses, then ran out and bought hand-held radios. Ours came with 7-V batteries and could transmit with 2 W of power. My radio's manual said that if I used a 12-V battery instead, the radio would transmit with 5 Ws of power. Naturally, I felt that I had to have that extra power, so I called a well-known battery seller and ordered a pair of 12 V batteries. Being an impatient sort of fellow, I also ordered two of their special "fast charger" units. We got the 12-V batteries and fast battery chargers and were able to transmit with 5 W of power. All was right with the world.

Fast forward to one year later. My wife told me that the 12-V battery in her hand-held radio was not holding a full charge. Even though we recharged our batteries every night, and the batteries usually lasted all day, hers was suddenly going flat by mid-afternoon. I figured it must be a fluke. Her battery must have had some flaw in it and we just had the bad fortune to get one of the rare duds. Three weeks later my battery started failing by mid-afternoon.

I called the well-known battery seller and ordered two more batteries. Here's how the conversation with that vendor went:

Slow charger and fast charger: Don't be in too much of a hurry

ME: "I noticed that the batteries have a 'recycle' emblem on them, and I was wondering . . ."

VENDOR: "We don't buy them back."

ME: "Okay. But since it says to recycle the battery, I was wondering what I should . . ."

VENDOR: "We don't take them back." Click. She'd hung up on me.

This conversation was only one of the problems I'd had with this particular vendor. The vendor's fast chargers had some sort of design flaw and failed to start about one time in every ten uses. I sent one of the chargers back, but the vendor returned it almost immediately, saying only that it worked "within specifications." All this led me to cease dealing with this particular battery dealer, whom I shall not name.

Freezing the battery: This doesn't work

I did not, however, write this column to blast a particular battery seller (well-known, state of New York). I wrote it to share with you what I've learned about batteries. Now, some of what I'm about to say is going to make me look pretty stupid. Just remember, you never learn unless you try (common sense notwithstanding).

NiCad batteries are not cheap, so after buying a second set for our two radios, I figured I really needed to learn something about making them last. Perhaps I could even learn how to revive our first set. I read books. I talked to experienced hams. I looked up battery information at various Web sites. I read suggestions from Internet news groups. I even sought the advice of a chemist.

There was a lot of information around. Unfortunately, not all of it was good, and it was often difficult to tell the good advice from the bad advice. I started with the easiest advice. I froze my battery. Okay, okay! I know it sounds dumb. But you have to remember that my head was buzzing with talk of "memory effect," NiCads developing "whiskers," and all manner of strange advice. It seemed plausible at the time. So I put my battery in the freezer--right next to the ice cubes.

Zapping the battery: This doesn't work either

Are you back? Have you picked yourself up off the floor, wiped the tears from your eyes, and finished howling, "What a dweeb!"? I will say the following in my defense. It actually worked! For about 24 hours. The battery actually held its full charge for one day. After that, it returned to its former, half-functional state. Subsequent re-freezings didn't help. The whiskers must have put on tiny little overcoats.

I moved on to a slightly more difficult--and infinitely more dangerous--suggestion. I zapped the battery. You've probably heard about this one. Briefly connect your NiCad battery to your car battery and it "explodes" those nasty little whiskers. Well, I was really reluctant to try this. I had a lot of conversations with the chemist (who actually recommended the procedure). I wore heavy gloves. I wore eye protection. I kept the NiCad in a sturdy enclosure just in case it exploded. And I made a closed circuit with my car battery for the briefest possible amount of time.

All I learned was how to make sparks. There are probably still stray electrons zinging around in my garage. Zapping my battery did not work. Whiskers 2, Gary 0.

If there is a way to revive failing NiCad batteries, that information is buried underneath a mound of disinformation, and I have yet to find it.

Editor's note: ARRL member Gary Hoffman, KB0H, lives in Florissant, Missouri. He's been a ham since 1995. Hoffman says his column's name--"The Amateur Amateur"--suggests the explorations of a rank amateur, not those of an experienced or knowledgeable ham. His wife, Nancy, is N0NJ. Hoffman has a ham-related Web page. Readers are invited to contact the author via e-mail, [email protected].

© 2002 American Radio Relay League