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Actually, this has been done and there is a thread on this forum. Once you find it, here is a little of the backstory ;) A while back I was giving a tour of my lab to some cybersecurity guys from another division at the Institute. These are the guys that get hired to penetrate systems. I...

There are two types of voltage curves. The first is usually expressed as voltage by Ah discharge or charge. This is a continuous load on the cell either to Vmin or Vmax. The other is an OCV (open circuit voltage) which allows a short time for the polarization to somewhat stabilze before the...

Was that while driving or or after the polarization had time to settle down?

BTW, the polarization is not done after 1 hour, but it is the method in the standard. When we do manufacturing tests on all the cells before binning for what cell goes through what test, we wait 24 hours after both the charge to 100% SOC (actual) and discharge to 0% SOC (also actual). Then we...

I would suggest that someone with the time and an OBD reader map out the voltages of each SOC. It can be cumbersome using the method we do to map a cell, but basically you drive it until you are down 10%, wait an hour, read the voltage. One thing to keep in mind when observations based on...

I take it you are in town for the eclipse? If so, we will only have 18 seconds of totality in SATX, but I suspect you will be heading to the hill country for the big show ;)

If you read my previous post on how to make the cells last virtually forever, you will see that I regularly charge to 85% SOC every day. This is just about 80% of actual capacity.

We actually do a 95% SOC and a 5% SOC pulse in our HPPC tests just to help calibrate the settings for our cycle life testing. The 0% SOC step is to find the voltage curve to Vmin. A pulse at 0% SOC would drive the cell below Vmin, so you don't want or need that pulse, nor 100% SOC in the HPPC...

Something seems off in these graphs. Why are they overcharging the cell? Vmax (maximum voltage) should be 4.2 V, but the graphs show going above this. When I program my cyclers, the safety limits are set to 4.25 V, and they will shut down if the voltage goes over this value. Did they have an...

Our cycle life testing is normally 3 different temperatures (25C, 45C, and 55C) and 3 different delta SOCs centered around 50% SOC (30%, 60%, and 90% delta). After 12 years of testing many types of chemistries, this is why I harp on the delta per charge (see previous posts) However, what we...

I respect that, but may I ask what data you are basing your analysis on?

I'm sorry, but I do not have enough data to say what will happen to your pack. As far as the HPPC, I hope I have given enough hints on what concerns me without directly saying what I have found. If you really want to see the data, convince your company (individuals cannot join directly) to...

I should also mention the resistance problem MAY NOT be real, but an artifact from what we had to do to the tabs in order to under go testing, but I'm not a big believer in that hypothesis right now.

You might want to review some of my previous posts about observations from actual lab testing at the cell level. What the BMS and modules do? I don't care. But I know after 12 years of cell testing what the cells are doing (and currently testing the SK One E805A from an actual F150 Lightning...

Not selling...just don't like the HPPC (Google it if you want) test below 20% SOC We test the cell directly at actual cell capacity (Vmax to Vmin static capacity before HPPC test). Even worse above or below 25C. We have finished characterization testing and are moving into calendar and cycle...

Based on what I've seen in testing this cell, I'm going to make sure I do not go below 20% of actual SOC :cautious:

If you can pull 80 A, you have duel OBC (On Board Charger) and you are only reading one of them. If you want to find the other one, collect all signals and look for something that matches. Sorry I cannot share the PID here since it was found in our testing of the Lightning (but it is there!).

I'd be more interested in knowing the normal charging profiles of those that have had a module problem. Another person on our campus had to lemon law his truck after the second module failure. I know he regularly charged to 90-100% with a high delta (let it run down to 20% before he charged it...

OEMs publish a 1st responder guide for every HEV/PHEV/EV that the 1st responders can pull up when they roll up to a scene. They also study these like they do other procedures and training aids. The very first step in these guides are the badging that will identify the vehicle as an EV. Then...

It might be a bad day for 1st responders if they have to roll up to your truck. 1st responder guides show the markings that will identify it as an EV. Without the markings, they may mistake it for a normal truck and cut into the wrong areas.