System76 Lemp9 Charging Thresholds

Jeremy Cheng
4 min readFeb 10, 2021

Maximizing Your Lemur Pro’s Battery Life with the Latest Firmware Update

One of my main gripes about the Lemp9 ever since I got it is the fact that the System76 firmware is unable to expose its charging thresholds which makes it impossible for people like myself that have their laptops plugged into a power outlet and a monitor for prolonged periods of time to even fathom the thought of preserving battery life. My usage pattern is so bad for the battery that within just 8 months from the time I bought the Lemur Pro, my battery started looking like this:

As you can tell, it’s super bloated. It was so bloated to a point that I was having trouble pushing down the space bar. Needless to say, it’s potentially dangerous for reasons I won’t go into here.

Sure, I am not dismissing the possibility that I had a defective battery but this is probably also partially caused by over-charging. Luckily, it was still under warranty and System76 replaced it for me free of charge. However, this doesn’t solve the whole problem. Without the ability to control charge thresholds, I am still at risk of causing the same issue over time and if nothing else, just reducing the life-span of this newly replaced battery faster than I would like. Unfortunately, according to their customer support, there was no ETA on releasing the charge thresholds control feature for Lemp9. So I was out of luck. But…

New Firmware Update Saves The Day!

I got notification for a firmware update sometime within the past 24 hours and in the release notes, it wrote:

“Charging thresholds”!!! I immediately went through the motions of updating the firmware and then proceeded to reboot the machine. After a fresh reboot, I went ahead and gave it a try.

I first checked what profiles are available just as reference so that I know what the presets are:

$ system76-power charge-thresholds