Charging rates

[Gros Ventre]

Ford's programming sets the fully charged voltage at 12.8VDC. If you look up the lead acid characteristics that correlates to 80% of fully charged. I believe Ford does this since AGM Batteries are more susceptible to overcharging damage. If you go into the software you can alter this. Is that a good idea? You be the judge. After replacing my battery with a NAPA unit and making no other changes, I've had zero problems in three years including cold winters. I can only speculate as to the cause for Ford Batteries, but the pattern seems clear. Is the Aux battery similar? Don't know, but I'm still using the OEM Ford Aux battery and no problems apparent.

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[Sig Oris]

You only get to pick two... but the list should be four. The fourth is the basic electro-chemistry. No matter what else you do, it will rule things. So long as the alternator is capable of putting out more than 30 amps, it'll suffice to keep the battery charged so long as you don't engage in a series of short on-offs. If you want to discuss the programming... that's another thing. Observing my system voltage I see no issue with programming on my truck except that the temperature compensation sensor is located outside of the engine compartment.

I was merely agreeing with his point about corporate America and I use current Boeing as an example vs the Boeing that built the B-52

 

[Sig Oris]

Just search based on description in the screenshot. I think it's got multiple listings.

Have you considered monitoring the AUX AGM battery? I see you get get an app that will monitor up to four batteries

 

[Gros Ventre]

I was merely agreeing with his point about corporate America and I use current Boeing as an example vs the Boeing that built the B-52

As to corporate America... got it, no sweat. Still, even they are captive to the elctro-chemistry... And that's what I think caught up with Ford on their 12VDC main batteries, they cut one corner too many in procuring those batteries!! My bet is that they specified or accepted a faulty alloying in their batteries.

 

[Snakebitten]

Have you considered monitoring the AUX AGM battery? I see you get get an app that will monitor up to four batteries

Technically it is monitoring the auxiliary battery. Or more accurately, it's monitoring both batteries in parallel as a 12V bank.

I doubt very seriously that the underhood AGM, if it were isolated from the auxiliary LFP, would be sitting at: (2 minutes ago)

 

[Gros Ventre]

Have you considered monitoring the AUX AGM battery? I see you get get an app that will monitor up to four batteries

Unless you're in the engine start cycle, you're monitoring both batteries since they're in parallel. If you want to monitor one battery, disconnect the other. The drains will be the same.

 

[Snakebitten]

Yesterday, 24 hours undisturbed

Today

That cheap little LFP gobbles the charging current and then, for whatever reason, helps that oem AGM present the electronics (22V buss) onboard the truck with a much healthier, and apparently stabler voltage.

 

[Spiffy]

Yesterday, 24 hours undisturbed

Today

That cheap little LFP gobbles the charging current and then, for whatever reason, helps that oem AGM present the electronics (22V buss) onboard the truck with a much healthier, and apparently stabler voltage.

This Bluetooth battery monitor. I can't get it to report real time. I open it just now after 5 4 hours sitting on a charger and it just won't update. Where do I kick it ?

 

[Spiffy]

This Bluetooth battery monitor. I can't get it to report real time. I open it just now after 5 4 hours sitting on a charger and it just won't update. Where do I kick it ?

I have the main under hood battery disconnected. I have a charger on it as well as the Bluetooth monitor. When the monitor shows full charge " if it will ever update" I'm going to pull it off the charger and see what it does through out the night. I'm waiting to go to bed. I can't do squat until the monitor reports. Full charge.

 

[Gros Ventre]

I have the main under hood battery disconnected. I have a charger on it as well as the Bluetooth monitor. When the monitor shows full charge " if it will ever update" I'm going to pull it off the charger and see what it does through out the night. I'm waiting to go to bed. I can't do squat until the monitor reports. Full charge.

When I did my "wetting down" charge on installing the NAPA replacement battery three years ago, the final battery voltage was about 13.4VDC. The truck system then ran that voltage down to 12.8VDC over the next hour or so... As I believe the truck is programmed to operate.

 

[Vater]

What is the voltage that my truck is supposed to charge at?
I'm suspicious that my truck is charging too high.

As mentioned by others here. AGM is about ~ 15v charging and has a resting voltage of about 12.8v to 13.2 when fully charged. Flooded cell is lower with AGM having higher charge and float voltages.

 

[HammaMan]

Are these voltage drops engine off drops? Or BMS reduced charging events?

Edit: never mind. I didn't snap that was a week graph instead of a single day.

Would love to see each day graph

Still looks highly unusual. That appears to be parasitic loss until just about everything sleeps.

@Spiffy do you have massage seats and are they currently both working (check)

 

[Gros Ventre]

Charging depends partly on temperature. The programming for your truck will settle out at 12.8VDC in the summertime. This represents about 80% full charge which is what Ford decided to program. I think because AGM batteries are more susceptible to overcharging damage. The temperature compensation sensor is located out in the pax side mirror. In wintertime you'll see as much as 15.2VDC. There is a higher charging voltage for colder temperatures. I've seen 15.2VDC steadily in 0ºF weather across hours of driving.

 

[Spiffy]

Still looks highly unusual. That appears to be parasitic loss until just about everything sleeps.

@Spiffy do you have massage seats and are they currently both working (check)

No i don't have massage seats.
I started thinking the same thing after looking at my chart. The rate of discharge is very consistent then just stops. Someone posted a couple of pdf files with very detailed information about ford's charging and battery management algorithm.
I'm sorry for forgetting who that was but thank you!
Anyway I read that load shedding when the battery is in an unusual state of discharge happens. Certain systems have priority and others are ranked as non essential.
Looking at my graph over several days the state of discharge stopped at exactly the same voltage. Then there is a slight bump up.

I'm trying to eliminate anything like batteries. According to the instructions on isolating parasitic loss. To do it correctly its a complicated procedure, best done with help. Pulling fuses and such.

I'm still trying to isolate possible battery issues. Last nigh I disconnected the motorcraft h7. I put it on my smart charger until full. 13.5v and 100%. Compared that with my scanner. I then connected the battery monitor. I left it overnight to record at least 8 hours. Got up about hour ago. "No work day, video game until 3 am" lol
Unfortunately my connection to the battery failed so I missed the recording.
I'm less suspicious of the battery now.
Even if it turns out I have random draw I don't know why it just started. Haven't modified the truck.
I'm wondering if by chance it took a recent update. I did recieve an update about the time this all started but it failed to install and finally timed out because I didn't provide the right conditions.
I know my truck is constipated with updates. I was going to set time to do them but got sidelined with this current issue. It's dam cold in the morning and don't have remote start.
Maybe all this will resolve with a fresh set of updates.

BTW. I'm actually having fun trying to figure this out. I'm hired to find intermittent electrical RF interference in aircraft, like why does the fuel gauges show empty when the electrical operated flaps are at 15% only on approach to landing while keying the mic.
These things NEVER show up in my hangar!! They don't replicate on the ground.

 

[Spiffy]

Even though I didn't get a good recording. I think the monitor is not working.
After the fully charged battery sat 12 hours it showed 12.6v. .3 down. Unfortunately that means I have a current drain. Bummer.
I now have two choices. Both are time consuming. One is to completely update the truck. I'm going to reach out to rugdraw and see where it's at. A fresh update might fix things.
Second is to do the parasitic test.
I need to find the pdf's. The link is somewhere in a couple of my posts.

Snakebitten... you thought I could benefit from disconnecting both batteries. You said it will reset shift. Not that I need it. Perfect transmission shifting. But what else gets reset?

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