Not linear, I could work on something
I got my 12th gen 13 in December `22.
tlp-stat output is as follows:
/sys/class/power_supply/BAT1/cycle_count = 196 /sys/class/power_supply/BAT1/charge_full_design = 3572 [mAh] /sys/class/power_supply/BAT1/charge_full = 3219 [mAh] /sys/class/power_supply/BAT1/charge_now = 2873 [mAh] Capacity = 90.1 [%]
I’m a bit disappointed in the degradation which has been quicker then I’ve experienced with other devices
Hi! I got curious about others’ experiences and views on the topic of battery degradation, and found this thread.
I haven’t read it all. I’m on Windows 10, and don’t have the full stats because I managed to lose everything in July 2022 to BitLocker, which was enabled without my consent or knowledge, when I initially installed.
Anyway, this is a Batch 9 1135G7 with 32GB of Crucial DDR4-3200 and a 2TB ADATA SX8200 Pro.
I’ve run this laptop hard, and before I started hibernating it instead of sleeping it, it would often drain itself hot in my bag because of the Windows sleep bug, whatever it is. I’ve done multiple charge cycles per day fairly often, and when on battery it’s typically drawing 20-30w: I’m doing intensive things or have too much open.
I’ve primarily been using a 120w Spigen USB-C charger for most of a year for charging (100W PD contract), and often used it at full tilt while charging it, so maximal battery heat – though I live in the UK, so it’s not the hottest.
HWINFO64’s estimate shows me around 17% degradation:
Here’s a graph of the historical data available to me from that report.
I’m not surprised or disappointed, particularly: I’ve run this battery hard without a charge limit. Once this battery is spent, I will probably be at the point of wanting to upgrade to 13th Gen or to a Ryzen board, and I can probably then upgrade to a 61wh battery.
Just an update.
The laptop and battery are 18 months down the line. I usually run connected to power and have the ‘Battery Charge Limit’ set to 78%.
Over the last 6 weeks the wear had averaged around 4.7% with a recent high of 6%. Being the beginning or a month I decided to recalibrate by running down the battery, then powering on again after some hours powered on set the BCL to 100% and drained again.
The wear now, for the last 24 hours has gone from 3.8% to 3.7% with the BCL still at 100%
The wear is technically negative if I account for the data that says it was 3.4% when first tested and 2.9% a week later.
- The dark blue line is the lowest recorded each day.
- The green line is the expected wear given the specs of 20% after 1000 cycles i.e. 2 per 100, given a 2.9% assumed start.
The graph is only for this year to 30th Sept.
The drops in Sept occur after:
- I have the battery charge limit [BCL] set to 90% after a full discharge and 100% charge
- I usually use with power supplied (99% of the time)
- Sometimes I forget to switch the supply on and the battery drops
- I connect power and the after it has recharged to my BCL the wear appears to have dropped.
- Set the BCL to 87% and a few days later forget to switch power on
- I recharge to the new BCL and again shortly after the battery wear drops even further.
Of course the current 3.7% could be the real wear but ideally after 73 cycles it should be approx 1.5% (73 cycles)
Just to say that the battery does not improve, there are many arguments that calibration can extend the ‘life’ of the battery.
The battery, in this case, is a set of 4 x 4.2 cells. However the unit that is bought as the ‘battery’ has a Battery Management System built into the case, this can be calibrated to update the measurement algorithm.
Note I have a battery that is over 19 months old, the wear of which I record daily. Upon receipt the wear was recorded as 3.4% and went down to 2.9% after a week.
Yesterday it when from a low of 3.6% to 5% in 24 hours so I set the Battery Charge Limit from 78%, my usual level to 87% then reset it to 78%.
I powered off for the night and this morning the wear records as 3.3%, though 3.5 after typing this entry
Calibration was never meant for battery life improvement (if that’s what you were looking to say), it’s meant to provide improved reading of the actual capacity of the battery. i.e. “to get an accurate reading” in the quoted message.
Yes, thanks, I was just stating/confirming that is my understanding, prompted by an argument elsewhere.
Just to confirm the trend.
Until two months of use, after receipt in Feb (2022) I had used the laptop a lot on battery without much checking. Then in July I accessed the cycles.
have monitored regularly since July 2022 and when the ‘wear’ rises ‘out of character’ I recalibrate the battery.
Around once a month I do a run down to zero and recharge to 100%
Generally I have the battery charge limit at 78%
Sometimes I intentionally or accidentally drop it a bit lower or raise the BCL to 87% and invariably I get a very low wear reading
The following graph is just of 2023.
I’ve started the ‘Spec Wear’ base at 2.9% as that was ‘the low’ after a week March 6th 2022 (see first graph)
1 year and 5 months in, I’m down to 87.6% of original capacity. Large drop happened after about 8 months of usage and the battery stayed around that mark since.
Can we do Y-axis starting at 0 for these charts?
In the case of capacity, I think starting from 100% is fine. Alternatively, see it as 0% wear at 100% capacity. (i.e. 100% is the starting point expected for new battery OOTB).
Have you re-callibrated the battery after the drop?
I note the 2022-07 reading was maybe 99%, so maybe only a 11.4% drop. My battery ‘started’ at 3.4% wear.
OH! and how many cycles has the battery gone through. A drop of 12.5% would equate to some 625+ cycles
An unexpected drop in wear recorded, the lowest ever @ 1.9%. It seems a low charge, in this case 66% may, again, have precipitated this.
Below is a graph of just this year until 27th Nov 2023
For tables of data :-
Have you recalibrated the battery, I tend to do this once a month.
5.1% wear at 36 cycles on my 4th batch 11th gen Intel. However the battery pack is slightly swollen. My battery hasn’t seen a lot of use until the end of 2022. I’m considering to replace it with the new 61Wh pack when it’s back in stock.
Regarding the swelling: If the swelling collapses under a light touch it could just be air under the plastic skin.
Regarding the wear: Have you calibrated by a full discharge and recharge over a couple of days etc.
I’d say in my case the puff is clearly inside the cells (i.e. not just under the plastic wrapping) but not really that solid (obviously I didn’t poke the cells, nor do I dare to… just my estimate). Again, the swelling is very slight. Visually the battery still has good clearance from the input cover.
I didn’t intentionally run a slow discharging/charging cycle as is usually recommended to calibrate the battery gauge. However it did see a few full cycles in the past two months, and the 5.1% wear level estimate doesn’t seem off to me judging from the run time.
You are allowed to touch them, just don’t apply a lot of force (or sharp objects) to them but knowing if they are under a lot of pressure or just barely not flat tells you a lot about how bad it is.
Mechanical violence is in my experience the most reliable way to have them perform “energetic displays” XD. Massive overcharging and shorting and so on can produce results too but a good stab with something sharp and conductive gets the job done most of the time as long as the cell has enough charge (which is probably also why some newer battery controllers also discharge the cells to 0 when they go into sudoku mode).