Second battery has failed - Ford BMS is crap

[Calson]

The factory battery needed to be replaced at 1,666 miles, Now at 4,026 miles the replacement battery needs to be replaced. The car battery was dead and when I attached a battery charger the truck battery showed a SOC of 4%. After 8 hours I got the battery up to 93% SOC. The next morning I reattached the battery charger and it showed the truck battery as having a 44% SOC.

I now find with my $65,000 truck that I need to carry around two jump starter batteries and jumper cables to go anywhere with my truck. The Ford battery management system was designed by clowns supervised by monkeys. Battery life is drastically shortened with the full discharge that the BMS is allowing to take place. This is a problem with the Ford programmers and not the battery as such.

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[EL5_Zero]

Is your truck a 2024? I thought they fixed the software issue causing the batteries to drain when powered off.

 

[Scoobtay]

Powerboost?

 

[HammaMan]

How long before interactions? Days? Weeks? Sounds like something isn't sleeping if the next day it's eaten 50%

 

[Snakebitten]

In another thread he mentioned that his truck has sat for 15 months.

That's not good for a battery in any vehicle.

 

[PPK]

Well.. the AGM battery can have a dead cell in it.. nothing wrong with that cell.. except you need to charge the battery a lot harder to get that cell back on the chart. normally you will get a few years out of each unit...

 

[Calson]

What is not good for starter batteries is a deep discharge of more than 50% SOC. Deep cycle and lithium batteries can survive that situation but not flooded lead acid or AGM type ones.

With my motorhome I had two 100 Ah lead acid batteries that provided 100 Ah of usable power at 50% SOC. I replaced them with lithium phosphate batteries that could be discharged by 90% without damage to the battery. This gave me 180 Ah of usable power from the two batteries.

The Ford BMS is supposed to shut off every power drain item after at most 60 minutes and prevent a deep discharging of the battery. Obviously that is not happening.

I decided to replace the Motorcraft H6 battery with an Optima H7 battery as the Optima is designed to allow for deep discharges and function in part as a "deep cycle" battery.

With dozens of vehicles over the past 60 years batteries have failed at times but the self-draining was never a problem. In the case of the new Ford there are substantial parasitic loads on the battery and Ford decided that programming would cope with these loads. Ford does put a higher capacity H7 battery in its Limited and Platinum trucks so its people are aware of the problems.

 

[CoolCoyote]

The Ford battery management system was designed by clowns supervised by monkeys.

I hate to break it to you, but you've just described all of Ford Motor Company.

 

[Graygoose2021]

Hate to say it, the Opimas aren't what they used to be neither.

 

[Gros Ventre]

Deep cycle lead acid batteries are physically constructed differently than Starting batteries. The issue is that the discharge vs charge products are different sizes. So if the battery isn't constructed to allow this change in size, a flexing of the constituents occurs. A starting battery is designed to provide relatively short bursts of power, so the plates are packed together and not set up for flexing. On the other hand the deep cycle batteries are set up to allow this flexing. Submarine batteries are routinely discharged and periodically a test discharge is done to parade rest. They do just fine. There are some things you can do to max out the battery life: Wetting down charge on receipt, top up with truly pure water (flooded cell types), each fall clean up the top of the battery, and do a low rate, long term charge at least each fall to drive off sulfates. I've had a battery last 8 years this way. I have installed a dashboard voltmeter in my Powerboost. The Ford programming of system voltage is on the mark for lead acid batteries (Note: I have little faith in the computer driven per centages of charge.). The exception to this is the temperature sensor driving system voltage is not inside the engine compartment, and so in cold weather the battery is overcharged because the sensor keeps the voltage higher than needed for float during long fully warmed up drives. I'm talking hours on the road at highway power and in temps below zero. Snakebitten remarked that batteries don't like to sit around... He's right on.

 

[My 2ND Ford]

Ford does put a higher capacity H7 battery in its Limited and Platinum trucks so its people are aware of the problems.

My 21 Job 1 Platinum came with an H6 from the factory.

 

[My 2ND Ford]

In another thread he mentioned that his truck has sat for 15 months.

That's not good for a battery in any vehicle.

Well ladies and gentlemen, there's your problem! If that is truly the case, then he ruined his own battery.

 

[Gros Ventre]

Well ladies and gentlemen, there's your problem! If that is truly the case, then he ruined his own battery.

If it really sat without running for 15 months... that likely did the battery in... On the other hand, I have concluded Ford has bought some poorly constructed batteries. I replaced mine at 4 months with an off the shelf catalog sized battery (NAPA) and not a peep in the 26 months since.

 

[My 2ND Ford]

If it really sat without running for 15 months... that likely did the battery in... On the other hand, I have concluded Ford has bought some poorly constructed batteries. I replaced mine at 4 months with an off the shelf catalog sized battery (NAPA) and not a peep in the 26 months since.

I ran a Napa store for years and I sold a lot of batteries. A typical lead acid battery doesn't mind
sitting on a shelf if it is put up with a full charge . It will typically last a good 12 -15 months and only need a good deep charge to bring it to 100%. But if a battery was left in a vehicle and kept in a state of full discharge for any length of time, then that would be the death of it. It truly is possible that Ford got a bad batch of batteries and with the chip hold that was going on, damaged the batteries enough that they developed problems.
These new vehicles are energy pigs, they develop all sorts of problems when voltage drops too low, wether its from poor charging performance or battery output while parked.

 

[Atlee]

My 21 Job 1 Platinum came with an H6 from the factory.

My MY22 Job 1 XLT PB came from the factory with a H7 battery with 800 CCA. 2+ years in, it's still doing fine.

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