I've got one set of dead batteries upgraded and tested and now attention turns to a different set of expired batteries. I bought this refurbished Dell Latitude E6230 several years ago intending to take apart and use as a robot brain. I changed my mind when it turned out to be a pretty nifty little laptop to take on the go, much smaller and lighter than my Dell Inspiron 7577. With lower specs than the 7577, it also had longer battery run time and its performance didn't throttle as much while on battery. It has helped me field-program many microcontrollers and performed other mobile computing duties admirably.

I retired it from laptop duty when I got an Apple Silicon MacBook Air, but I brought it back out to serve as my introduction to running virtual machines under KVM hypervisor. Retired laptops work well as low-power machines for exploratory server duty. Running things like Home Assistant haven't required much in the way of raw processing power, it was more important for a machine to run reliably around the clock while stashed unobtrusively in a corner somewhere. Laptops are built to be compact, energy-efficient, and already have a built-in battery backup. Though the battery usage pattern will be different from normal laptop use, which caused problems long term.

Before that happened though, this Latitude E6230 developed a problem starting up when warm. If I select "restart" it'll reboot just fine, but if I select "shut down" and press the power button immediately to turn it back on, it'll give me an error light pattern instead of starting up: The power LED is off, the hard drive LED is on, and the battery LED blinks. Given the blinking battery LED I thought it indicated a problem with the battery, but if I pull out the battery to run strictly on AC, I still see the same lights. The workaround is to leave the machine alone for 20-30 minutes to cool down, after which it is happy to start up either with or without battery.

But if the blinking battery LED doesn't mean a problem with the battery, what did it mean? I looked for the Dell troubleshooting procedure that would explain this particular pattern. I didn't get very far and, once I found the workaround, I didn't invest any more time looking. Acting as a mini-server meant it was running most of the time and rarely powered off. And if it does power off for any reason, this mini-server isn't running anything critical so waiting 20 minutes isn't a huge deal. I decided to just live with this annoyance for a long time, until the second problem cropped up recently:

Now when the machine is running, the battery LED blinks yellow. This time it does indicate a problem with the battery. The BIOS screen says "Battery needs to be replaced". The Ubuntu desktop gives me a red battery icon with an exclamation mark. And if I unplug the machine, there's zero battery runtime: the machine powers off immediately. (Which has to be followed by that 20 minute wait for it to cool down before I can start it up again.)

I knew keeping lithium-ion batteries at 100% full charge is bad for their longevity, so this was somewhat expected. I would have preferred the ability to limit state of charge at 80% or so. Newer Dell laptops like my 7577 have such an option in BIOS but this older E6230 did not. Given its weird warm startup issue and dead battery, low-power mini-server duty will now migrate to my Inspiron 7577.