%SOC X usable battery X consumption (mi/kwh) = a much better guess o meter value
granted, you are right you don't need it every second....but darn right I'm going to use it a lot when pushing the range which I will have to regularly do.
%SOC X usable battery X consumption (mi/kwh) = a much better guess o meter valueDoes no one look at the colorful gauge that is on the left side of the ring on the left of the screen to get the SoC of the battery? It's broken into segments and it's easy to see roughly where your battery is in broad terms (100%, 75% 50%, etc). I get wanting that exact % value to be shown, but the rough SoC is displayed, if only graphically. Does that not cut it for most people? How did we survive all those years looking at a gas gauge that wasn't reading tank contents to the single digits?![]()
So, the question is, when exactly does the big battery charge the little battery?There have been references to the Lightning being designed so as to provide charging to the 12 volt battery as long as the vehicle is plugged into an EVSE.
I think it is now proven that this is not the case. Unfortunate, but at least we know.
Make me wonder if they continues to be a major issue, that Ford will do a recall and do something similar.In the vast majority of modern EVS, the computer will fire up the DC to DC converter when the ignition is turned "on". There is some loss involved in chopping the voltage, so this prevents excessive parasitic draw from the high voltage battery when left sitting over time.
Based on evidence at hand, there is little doubt this is the scenario for the Lightning. In some vehicles, this is a computer-controlled sequence that was later addressed with over the air updates. If Ford built the vehicle with this capability, it can be addressed. Having seen much of the way this vehicle is put together now, however, I think it is more likely a "dumb" relay. A lot of those are Incorporated in this system. This type of relay cannot be upgraded over the air, so the fix would have to be incorporated into later models of the vehicle.
A simple fix would be to increase the size and power of the auxiliary battery. If I still had a Lightning, I would probably put in a Zero Gravity lithium-ion Harley-Davidson battery in its place, and I'm betting it would solve the problem permanently. These batteries idle at a higher voltage, and I believe would keep the electronics in the truck very happy. It would not be subject to the voltage sag that appears to be tripping the "save myself" mode that the truck is going into.
RIP, you are the best. I have my motorcycle battery on a tender for the winter. That tender should be enough to do the job, correct? (it is just a little motorcycle one.....) Figure this will be an issue for me at some point.....25 years ago when I was building EV conversions we incorporated a simple 12 volt battery charger connected to the auxiliary battery that fed power off of one side of the HV battery charger. I got tired of having angry customers upset that their EVs would not start, so I fixed it with this simple solution.
Tesla went surprisingly long without learning this lesson, but now charges the 12 volt battery when the vehicle is plugged in. Rivian just flat copied that design with a bunch of other stuff, so they are covered. Anecdotally, the Lightning was supposed to have the 'charge-12-volt when plugged in feature' as well, but evidently either it does not, or it is not working.
For years GM also lacked that small additional charger. It's a bean counter thing. That little charger really racks up in price when you multiply it by hundreds of thousands of vehicles manufactured.
If in fact Ford did not include the 12 volt charging system in the vehicle while it is shore powered, it is actually a pretty straightforward aftermarket edition. Almost tempts me to come out of retirement.. 🤔
P.S.
An additional auxiliary charger is one way to address this issue. A simpler, and possibly more elegant solution is to just power the DC to DC converter anytime the EVSE is connected. I believe that is incorporated into GM's newest designs.