Same size batteries are not the same size

[ronburgundy]

This is mostly a public service announcement.

Ever been frustrated by electronic devices that won't respond consistently but have fully charged batteries?

I recently realized something that might be partly responsible. Batteries are not a uniform size. I have a clock that takes 1 AA, which stands upright in an open compartment with no spring. The tightness of fit is the only thing that holds it in. I recently changed the battery and the new one fell out a couple times. I measured against the old one of a different brand the new one is 1 mm shorter and about 1 mm less in diameter. I grabbed a third brand and it was 1 mm longer than the old one and thus 2 mm longer than the shortest. That seems like it could be enough to prevent a strong stable contact in some devices.

Part of the problem may be that AA batteries can be either alkaline, carbon zinc, or other types. They look the same and are seemingly interchangeable but unless you're paying close attention to your batteries you may not have noticed. Two of my batteries that are different sizes are both Panasonic, but one is alkaline and one is carbon zinc.

 

[Bronzeage]

I can see the reason for your frustration.

However, the critical dimension for drycell battery is the diameter. Almost every battery powered device uses spring tension contacts which should have enough travel to compensate for a small difference in length.

If we want to talk about battery conspiracies, we might ask what happened to B-batteries? No one wants to talk about that.

 

[ronburgundy]

I can see the reason for your frustration.

However, the critical dimension for drycell battery is the diameter. Almost every battery powered device uses spring tension contacts which should have enough travel to compensate for a small difference in length.

If we want to talk about battery conspiracies, we might ask what happened to B-batteries? No one wants to talk about that.

Or simple A size for that matter

Yeah, I know there is usually a spring, but not always, and some springs lack sufficient range or lose range over time. Also, the diameter differs too, which can make them hard to remove from compartments or in some configurations, push each other out of proper alignment if the cover isn't designed to hold them in place.

 

[barbos]

I have a flashlight which does not like certain NiMH batteries because '+' was not protruding enough.
Also in some cases battery compartment designed in such a way that it does not accept wrong polarity this could be a problem with such batteries too.

 

[Valjean]

Sometimes you need to put a couple layers of foil behind the negative end.

 

[Juma]

What is this nonsense? What crap are you buying?

 

[wally]

I can see the reason for your frustration.

However, the critical dimension for drycell battery is the diameter. Almost every battery powered device uses spring tension contacts which should have enough travel to compensate for a small difference in length.

If we want to talk about battery conspiracies, we might ask what happened to B-batteries? No one wants to talk about that.

Or C batteries for that matter. They mostly went away when transistor radios became available. B batteries are/were high voltage around 90 volts or so and provided the high positive voltage to operate vacuum tubes. The C battery was used to provide bias voltage to the screen grid of the tubes. the A battery heated the filament.

 

[barbos]

I have never heard about B-batteries, but google says they are 45 volts and looks like very long 9 volt battery.
https://en.wikipedia.org/wiki/Battery_(vacuum_tube)
looks like they had different voltages and sizes