The Ubiquitous, Indispensable CR2032 Battery

November 22, 2021

My Stages SB20 Smart Bike paired with Zwift just fine, but when I pedaled my Zwift avatar just stood there. After troubleshooting my Zwift account (had I failed to pay?), and my Windows gaming rig (the same thing happened when I logged in with an AppleTV), it finally dawned on me. After 6 months with this smart bike, the coin cell batteries in the Stages Power Meter (part of the Stages Bike), went dead. I popped in a pair of new CR2032 batteries (one on each crankarm) and, presto, my avatar chose to join the ride.

This happened just a few days ago. Also last week my Wahoo ROAM head unit displayed N/A where the power displays. My head unit was not waxing sarcastic at my lack of power, and there wasn’t anything wrong with my head unit. The battery in my Quarq power meter went dead (after 2 years of use). In the image above is where the battery goes in my Quarq power meter, and the image below that is what the rest of that process looks like: The battery is fixed by the battery cap (which screws on by hand), and a cosmetic cap (no tools to change this battery).

It was the same battery I needed in both power meters: a CR2032. This battery’s nomenclature works as follows: 2032 means its 20mm in diameter and 3.2mm in depth. The C announces the chemistry of the battery, which is lithium (as opposed to alkaline, silver, mercury, zinc). The R means it’s round. Its electrical potential is 3 volts.

It’s the most common coin or button cell battery in use today, and not just for bikes. You have CR2032 batteries for all kinds of things, and most folks can’t name half of them. As for my sport usage, I have this battery in my Zipp Vuka Shift AXS 90 wireless shifter extensions and, of course, in my Quarq and Stages power meters. This CR2032 battery powers your SRAM Blip Box.

This is the battery used in many electronic road shifters, including the SRAM AXS road shifters, and it's the battery in SRAM’s Eagle AXS and GX Eagle AXS controllers. It's also used by FSA in its electronic road shifters. This battery powers your Garmin Cadence Sensor, and is in the heart rate monitors made by Polar, Garmin and Wahoo Fitness.

This is also a common battery powering your key fob, your remote control, and it may well be on the motherboard of your computer. If you use a portable bank card reader, this is probably the battery that powers it.

It’s not a rechargeable battery, and if your device uses a coin cell battery it may not be this one. Shimano’s new 12-speed electronic road groupsets, the 9200 Dura Ace and 8100 Ultegra, use a smaller-sized CR1632. Timex’s IRONMAN watch uses a CR2016 (still 20mm across, but half as thick).

If you have pets or small children make sure and keep these out of reach. Still, I always keep a lot of batteries around: 9v for the smoke detectors, AAA and AA for all kinds of reasons. These coin cell batteries are cheap. I bought this package from Costco, I think it cost me $12. Before you curse out your device for failing, remember it may be the battery. If it’s for an endurance sport purpose, it’s most likely this one. Because of all the sports devices that use it, as well as the other household and automotive devices that require it, perhaps throw a package like this in the shopping cart when Thanksgiving or Black Friday shopping.

But not these batteries pictured here, I have come to understand, because the bitter coating Duracell puts on them interferes with (at least) Quarq's (if not others') capacity to send certain signals. (It's always something.) So, Energizer, Sony, Panasonic, anything (apparently) but Duracell! (There's an update on this.)