LFP to 100% Each Week—Assumptions?

[DuncanM]

As for me keeping a high SOC for emergency situations, it's an probability thing. The chances that I'll unexpectedly need a lot of range are very low. The benefit of a lower SOC is higher.

We just drove my 2022 TM3 RWD, 2032 miles and just arrived at our SE Arizona home. We've been here for 4 hours and the grid power to the whole valley just failed. $h*T happens. Luckily we have about a 50% SOC, but our car may be our refuge depending on how long this lasts.

We're in Portal AZ (Cochise County) Here's the outage map:

Map Viewer

ebill.col-coop.com

 

[DuncanM]

We just drove my 2022 TM3 RWD, 2032 miles and just arrived at our SE Arizona home. We've been here for 4 hours and the grid power to the whole valley just failed. $h*T happens. Luckily we have about a 50% SOC, but our car may be our refuge depending on how long this lasts.

We're in Portal AZ (Cochise County) Here's the outage map:

Map Viewer

ebill.col-coop.com

The power came back on after about 4 hours. I neglected to mention, in my quoted post, that an apparent lightning strike over the summer, when we were gone, fried all the GFI plugs in the garage and the garage door opener. Fortunately, the exterior GFI plug by the garage survived and I was able to get charging going through that. We also lost all the electronics in our family room/theatre room, despite them being unplugged.

 

[PianoAl]

Here's a cautionary tale: I have a Macbook that I rarely use. Thinking to keep the batter healthy, I got it to around 50% SOC, and set up a timer to charge it one minute per week (determined empirically). That kept it close to 50%, and it's been like that for maybe a year.

Today I needed the laptop, and started using it. After 15 minutes, BAM, it crashed. For a while I thought it was bricked. I plugged it in and saw that the SOC was 1%.

I'm guessing the Macbook's BMS was misestimating.

 

[stopcrazypp]

Here's a cautionary tale: I have a Macbook that I rarely use. Thinking to keep the batter healthy, I got it to around 50% SOC, and set up a timer to charge it one minute per week (determined empirically). That kept it close to 50%, and it's been like that for maybe a year.

Today I needed the laptop, and started using it. After 15 minutes, BAM, it crashed. For a while I thought it was bricked. I plugged it in and saw that the SOC was 1%.

I'm guessing the Macbook's BMS was misestimating.

I think it is because you used a manual method of maintaining the charge and if power consumption varied, your method can accumulate errors. My Lenovo Thinkpad instead has a way to set a upper and lower limit and keep it between that. I wish more devices allowed that (including Android; it's possible with rooting, but not on stock).