I've had my Casio G-Shock for about 8 years now. In that time, it's run out of batteries on me a few times. The first time, I spoke with a shop and they said they had to send it in to Casio to have the battery replaced. The cost would be around $70 and take about two weeks. I then asked if I could replace it myself and they said it was impossible. I checked on the internet and the batteries are CTL1616 rechargeable Lithium Ion watch batteries. At the time, they were impossible to buy online so the only option was to send it in to Casio. Now, you can get them on eBay and Amazon, but they cost $15/each.

On the other hand, you can get CR1616 lithium watch batteries which are the same size but non-rechargeable for about $0.60 each. When I asked a repairman whether I could use those, he said definitely not and they'd end up breaking the watch. Since I didn't want to spend the money and wait a few weeks to get my watch back, I decided that I'd open up my watch and do it myself. The worst case was that I'd have to buy a new watch which I was planning to do anyways. It went much better than I expected. The first battery replacement was about four years ago and I happily discovered that a single battery lasts a very long time, most likely due to Casio's excellent watch technology. Since then, I've been happily using cheap, non-rechargeable batteries quite successfully.

To ease some concerns regarding the electronic details, the CTL1616 batteries run at 2.3V while the CR1616 batteries run at 3V. I haven't had any problems running at the slightly higher voltage so far, and I suspect it's unlikely that any parts rated for 2.3V would not be 3V tolerant. The other concern I originally had was that the watch has a built-in solar recharger and the battery would get damaged from the charge circuit. In reality, the solar cell is so small that most likely, it only yields a few tens of microamps in sunlight. Having a charge current that low would likely be insufficient to damage the battery and if it did, it'd only be an additional $0.60 to replace it.

Of course all this is theory, but I've actually been running my G-Shock on non-rechargeable, 3V, lithium CR1616 batteries for about four years now with no problems. It keeps extremely accurate time and a single CR1616 battery lasts close to two years. So for those that have a G-Shock and are interested in saving a few dollars while voiding your warranty, here's how I replace my batteries with cheapo lithiums :)


0 #1 Manhar 2017-02-01 20:24
You will kill charging circuit as soon as you install CR1616.

Add comment

Security code