Modern car intelligent charging systems: Chronically undercharging battery?

[nobb]

It's been a while since I've bought a new car, all my previous vehicles were <2015 and I have never had any issue getting ~10 years out of the OE battery even up here in Canada where the winters get down to -40C.

However, I just picked up a 2024 Mitsubishi Outlander (similar chassis and electronics as a Nissan Rogue) and what I noticed was strange is that despite it being such a new vehicle, the resting voltage of the battery is pretty low at ~12.15V. Like with modern Nissans, it has some sort of intelligent Variable Voltage Charge System (VVCS) which is probably why it's not fully topping up the battery.

Also, it has a seemingly uncommon battery size: L3-EFB. Researching this it appears the "EFB" is some sort of enhanced flooded battery optimized for start stop applications where the battery may operate at a reduced state of charge. This vehicle does not have start/stop, so I don't know how necessary it would be in the future to replace it with another EFB rated battery? Would there need to be some sort of calibration process via a tool anytime the battery is replaced?

Any thoughts on this? Is there an easy way to disable VVCS and it is ok to do so? The vehicle has been starting just fine in the winter, but I can't imagine being at such a low charge good for the longevity of the battery. Dealer won't do anything because this is normal under their view.

 

[Patman]

If things have changed on newer vehicles I’m not experiencing that issue. I still have the original battery in both of my cars (2016 Civic and 2018 Corvette). Both cars get driven on long drives pretty much every time I get behind the wheel.

 

[Jetronic]

I'd expect that behaviour on any car that has a battery monitoring system

 

[Kalle.J]

Throw a chepo AGM in it, in the biggest size that fits. And forget it.
12.15V is not a healthy battery.

 

[John105]

My BMW battery is over 14 years old, not uncommon (made in USA by Exide but OE, I stupidly replaced the one that came with the car when it was 4, despite the dealer telling me it's not necessary [go figure but it was $280 back then and I said cheap insurance]). I would think the IBS is why it's that old, by not overcharging it.

If anything, the logic imho on modern cars extends battery life. Why is it undercharged? Voltage is only one criteria in the application. A battery can have high voltage, yet be unable to start the vehicle, why we have load tests.

 

[John105]

Throw a chepo AGM in it, in the biggest size that fits. And forget it.
12.15V is not a healthy battery.

I'd do a load test to know a little more. Testers are cheap and likely can even be borrowed. AGM not necessary and size doesn't matter. I guess I don't agree with anything you've said it's very arbitrary

 

[nobb]

I'd do a load test to know a little more. Testers are cheap and likely can even be borrowed. AGM not necessary and size doesn't matter. I guess I don't agree with anything you've said it's very arbitrary

It's still a fairly new battery, so everything tests fine on the battery tester. CCA is still higher than OE, internal resistance 4 m-Ohm, and like I said, starts fine even in the Canadian winters. But I know that having it rest at such a low voltage is not good for the life. But of course the dealership techs can't do anything about it because they'll hook it up to their battery machine and it also tests fine.

 

[Kalle.J]

I'd do a load test to know a little more. Testers are cheap and likely can even be borrowed. AGM not necessary and size doesn't matter. I guess I don't agree with anything you've said it's very arbitrary

AGM will absorb charge easier in general and especially in the cold.
Most places recommends 12.4V+ to minimize Sulfation.

 

[oilboy123]

I put my vehicles on a Noco 1 amp maintainer. Connected with a fused lead to batt that comes out of grille with duplex connector. I plug in everytime now. Sometimes the charger runs for several hours.

When I open doors, the batts get sucked down pretty quick. I feel they are really chronically undercharged all the time. Even when I come home, get out, and test batts they are usually not even close to 12.6 ish. Which after driving for more than a short winter trip is unacceptable. Even when I was doing a 30 mile each way it was still not great. JMO

 

[f355spider]

As mentioned above, the simplest solution is to put a ringed battery adapter (SAE) plug on the battery and connect to a battery tender periodically. I have four cars, two are garage queens and are constantly on a Battery Minder brand tender, and the other two out in the driveway get connected occasionally. My BMW batteries are 6 and 7 years old now...they regularly test fine, exceeding their rating.

With an SAE plug out the grill, it is a simple matter to connect up and not at all inconvenient to do once or twice a week.

 

[samven]

Did you disconnect the battery before you tested it. Modern cars have so many computers running and many of them have cellular connections to report driving habits and other parasitic drains the battery is never at true rest. Even if it is a small drain you will get a false voltage reading.

 

[SubLGT]

............the resting voltage of the battery is pretty low at ~12.15V. Like with modern Nissans, it has some sort of intelligent Variable Voltage Charge System (VVCS) which is probably why it's not fully topping up the battery.

What is the alternator charging voltage immediately after a cold start?

 

[D1dad]

Throw a chepo AGM in it, in the biggest size that fits. And forget it.
12.15V is not a healthy battery.

The charging system is set up for the sized battery the manufacturer installed. Too big of a battery defeats the logic of old when an alternator just charged. Pretty much why most cars come with less CCAs than what cars did 20 yrs ago.
I challenge anyone with a new car, spend $20 on an ancel tester and you’d be amazed how undercharged your battery is. Use a load tester…same results. Long drives or not.

I charged the battery to full on my wife’s 24, drove to Lexington from northern Ohio, 4hrs each way and spent a week for business. When I got back her agm was at 67%. The alternator works as it supposed to, which is just enough. I have an 18 and 21 and installed flooded batteries and they stay topped off better than her agm. This isn’t a knock on agms, just the facts.

 

[JimPghPA]

Get one of the modern barrery testers. You have to measure at the battery with them. On the connectors at the battery is good enough if the connections are clean and tight. Amazon sells them. They are nice to have. I have detected a few batteries of relatives vehicles that neded replaced before they had a no start, by using mine.

The modern battery testers are really nice. They will show the state of charge, actual CCA, internal resistance, voltage, and some also have other features.

It the SOC is > 80 % after sitting unused for about a day, then everything is good.

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Note, my 2016 Honda CR-V will maintain a higher battery voltage if anything electrical ( besides the engine required power ) is turned on such as Headlights, AC, heated seat, sound system. Turn on any one or more and it has a higher idle speed, and maintains a higher battery voltage.

I don't know if other brands do that. But it is something to check.

 

[Nick1994]

Pop the hood and take the keys inside the house for an hour and come out and check the battery voltage.

My Grand Cherokee would show low voltage if I went out to it, unlocked it, and popped the hood. It would wake up all the electronics. But if I didn’t let it wake up, the voltage was fine.

 

[D1dad]

My son in laws 2023 company truck (f150) is constantly telling him through his app that his battery is low. He drives from home to work and back most days, 13 miles each way. He isn't allowed to so much as check the oil, due to liability so he's just waiting for the battery to crap out. I'm currently in NJ for a few weeks for work, so my cars setting at home on a battery minder 2012 and another car is setting on a pro logix pl2140. I have a couple of pulsetechs, but I haven't used them enough to trust them for 2 weeks yet.

 

[Wheel366]

My son in laws 2023 company truck (f150) is constantly telling him through his app that his battery is low. He drives from home to work and back most days, 13 miles each way. He isn't allowed to so much as check the oil, due to liability so he's just waiting for the battery to crap out. I'm currently in NJ for a few weeks for work, so my cars setting at home on a battery minder 2012 and another car is setting on a pro logix pl2140. I have a couple of pulsetechs, but I haven't used them enough to trust them for 2 weeks yet.

You're in NJ? Sorry to hear! ;-)

 

[D1dad]

You're in NJ? Sorry to hear! ;-)

LOL! Good folks in (Princeton NJ) but different from Ohio and the Midwest no doubt. Do you ever get used to having to drive 4 miles to make a left turn so you can come back 2 miles?

 

[Wheel366]

LOL! Good folks in (Princeton NJ) but different from Ohio and the Midwest no doubt. Do you ever get used to having to drive 4 miles to make a left turn so you can come back 2 miles?

No man, I don't get used to it but I am further north so I don't have to deal with it so much but still have to a little.

 

[PontiacHO]

Not sure it’s this way with current vehicles but….our 2010 BMW 3 series was supposed to have the “ECM reprogrammed” (?) to allow for charging a new battery. I didn’t do that when replacing the battery because any form of voltage regulation is supposed to sense the voltage and amperage needed during charging.