Any way to tell physically or through diagnostics how old my 12V battery is?

[takingittothemax]

Really happy with my 2014 SEL Hybrid I bought a few weeks back.

 

Got a Bluetooth OBD-II thingo and Forscan Lite, and it says the battery age is basically 6 years. I looked at the car's CarFax service history, and I can see it was regularly serviced and checked, but there's no mention of whether the battery was ever changed.

 

Is there a way of figuring out whether it has been changed? I had a quick peep under the floor, and the battery looks really new, but I'm assuming they all look like that because they're not next to the engine and exposed to the elements.

[plus 3 golfer]

There will be a date code on the battery. You can search internet for how to read code for Motorcraft battery but it appears you may have to remove battery to find the code.  
 

Your SOC is showing 4%.  I would put the battery on a charger overnight (or until charger indicates battery is fully charged) and then see what the SOC is after charging. Alternatively, you can leave the car in ready to drive mode (turn off all accessories) in an unclosed area for several hours as the 12 V battery will continue to be charged by the DCDC converter.  When the  HVB charge reaches a low set point level, ICE will start to charge the HVB.  
 

The point being that the higher the SOC reaches in charging overnight, the newer the battery.  For example,  when my 2nd battery was about 700 days old but the battery age in FORScan was about 1500 days old (battery age was not reset by dealer when new battery put in), my SOC was generally showing in the high single digits, low teens but after full charge would be around 90%. But, the SOC would after a few weeks would fall back to around the single digits. About 20 months ago, I reset battery age with FORScan and SOC would then be around 60%.    
 

Currently, when I fully charge my battery, SOC will be about 60+% and actual battery will be 5 years old next month.  My SOC generally shows in the 40-55% range.  I recently reset my battery age to zero with a manual procedure (to see if the procedure worked without FORScan).

 

 

[fbov]

13 hours ago, takingittothemax said:

Really happy with my 2014 SEL Hybrid ... the battery age is basically 6 years.

My 2013 made it to January on the original factory battery, 7 years, 3 months, with no issues. I no longer own the car, but suspect it's still working fine, unless the car's been sitting. I'd look into the car's history to see where it was  in the country. Heat matters. We get great battery life in upstate NY, Plus 3, not so much in AZ. 

 

Stay well,

Frank

[C-MaxA2]

Given complexity of changing the battery (it's not just open the hood and get at it...it's in the trunk and you have to deal with a lot of different screws to take apart stuff to get to it) and the fact that it's a fairly rare battery (Costco doesn't have it) I'd just say get a dealer or knowledgeable repair shop to replace it.  Why risk finding it dead at the wrong time.  Is the gamble worth it?

 

Oh - and you have to 'reset' the battery age correctly for it to live a long life.  Do you know who to do that?

 

I replaced the battery after I bought our two used C-Maxs.  Worth piece of mind.  

[plus 3 golfer]

Ford Quick Lane runs specials on the battery all the time.  Currently, they have the MOTORCRAFT® TESTED TOUGH® MAX BATTERIES STARTING AT $129.95 MSRP.* plus tax and installation with a 3 year replacement and 100 month prorated warranty.  For about $20 installation (2015 price) or so, IMO, it's not worth DIY.  They will also test your battery for free.  Tire rotation is $10 total.  So, I go about 15 minutes before they open, get tires rotated, battery checked, drink a couple cups of coffee and eat two doughnuts all in a little over an hour. Best $10 you can spend (Nov. 2019 pricing). ?

Edited May 20, 2020 by Plus 3 Golfer

[takingittothemax]

1 hour ago, Plus 3 Golfer said:

Ford Quick Lube runs specials on the battery all the time.  Currently, they have the MOTORCRAFT® TESTED TOUGH® MAX BATTERIES STARTING AT $129.95 MSRP.* plus tax and installation with a 3 year replacement and 100 month prorated warranty.  For about $20 installation (2015 price) or so, IMO, it's not worth DIY.  They will also test your battery for free.  Tire rotation is $10 total.  So, I go about 15 minutes before they open, get tires rotated, battery checked, drink a couple cups of coffee and eat two doughnuts all in a little over an hour. Best $10 you can spend (Nov. 2019 pricing). ?

 

Sounds mighty tempting because the battery went flat overnight. Needed to get it jump started. I'll probably do this once the pandemic peters out a bit.

 

In the meantime I think I need to get a portable battery charger...

[plus 3 golfer]

Oops that’s Ford Quick Lane. Yes, you need to try charging overnight to see if it will hold charge and then you can monitor SOC with FORScan. If it holds charge, I’d reset battery age which might get the SOC up.  
 

With only 4% SOC, the normal battery drain (up to 50 mA or 0.05 Amps but should be less) when car is off could result in a no start if the car has not been run for several days.  The Ford battery is rated 43 Ah when new.  So, 4% SOC means the battery capacity is around 1.7 Ah before voltage drops to IIRC 10.5 V which is defined as zero SOC. 1.7 Ah / 0.05 A = 34 hours.    The car will likely still start at 10.5 V as modules can still operate at 10.5 V.  So, as long as the there’s still enough power in the battery to close the HVB contacts, the car will then start. 

Edited May 20, 2020 by Plus 3 Golfer

[jestevens]

It was time to change mine two Februaries ago when I had to use the key embedded in the FOB twice because the doors wouldn't unlock.  I could find the battery slightly cheaper online but then you also have to deal with shipping, plus with no heated garage wrenching on the thing for a half hour in the cold just didn't seem appealing to me.  I second the notion of using the Ford service special.

[takingittothemax]

Yeah, I think I might get the battery changed once the kids are back in school and the curve is very flat. My lithium-ion battery jump starter thingo is arriving on Tuesday, so I'll be starting the car every day -- something I usually have to do anyways because of street cleaning.

 

21 hours ago, Plus 3 Golfer said:

With only 4% SOC, the normal battery drain (up to 50 mA or 0.05 Amps but should be less) when car is off could result in a no start if the car has not been run for several days. 

 

Thanks for the maths. I've been checking it since the jump start and driving it around town for errands yesterday and it seems healthier. SOC was up into the 40s.

 

When the jump starter arrives, I'll try to improve that.

 

The battery may have died because I ran a whole bunch of diagnostic tests in accessory mode the night before...

[takingittothemax]

I'm wondering, is there any danger/downside to resetting the battery life setting in the car without knowing for sure how old the battery is?

[plus 3 golfer]

My thoughts on resetting battery age:

1) The BMS estimates the Ah losses by integrating the current flowing through the negative cable of the battery.  Thus, as the battery ages, the Ah capacity of the battery declines.

2) The goal the charging algorithm is to maximize the life of the battery by regulating the charging current flow into the battery by adjusting charging voltage as the battery is being charged.  The issue are that as the battery ages, each of the 6 cells likely age differently (develop different resistance) and that the estimated battery capacity is accurate based on the battery age parameter and the new battery capacity is around 43 Ah.  
3) Because the cells will have different resistance, the voltage across each cell will be different for the same current flowing through the battery.  Thus, some cells given a standard charging algorithm (not BMS) may be overcharged (too high a voltage) and some cells undercharged (too low a voltage). Undercharging reduces overall Ah capacity for each charging time period and continual undercharge causes sulfation.

4) The BMS based on the estimated Ah capacity will set the charging voltage to a charging  rate based on the current Ah capacity of the battery. It appears from my observations that the BMS does not have a constant current, bulk charge phase but goes immediately to the constant voltage, topping charge state which generally would begin once the battery capacity is around 80%.  

5) So, if battery age was not reset when a new battery was installed, it appears that the BMS will use a constant charging voltage that is too low and the battery will likely never be charged to its capacity because the car is generally not run long enough (driving time and frequency of driving).  By resetting battery age (even for an aged battery),  charging voltage increases slightly (0.1 - 0.2 Volts) based on my observations and thus adds more charge to the battery than absent the battery age reset.

6) The only downside,  IMO, to resetting battery age to zero could be overcharging of weaker cells (shoving high current through those cells with higher resistance).  If the weaker cell reaches 100% of its lowered capacity when the stronger cell is significantly less than 100 % charged, it may cause excess gassing.  This is unlikely given the small increase in charging voltage and that the BMS is not a fast charger (takes many hours of driving time to fully charge).  Again, from my observations based on fully charging with a battery charger and actual driving three times for 28-30 hours in 2+ days, the BMS will not fully charge the battery unless one drives many hours over a several day period.

7) In summary, there needs to be a balance between preventing sulfation due to continually undercharging stronger cells and gassing due to overcharging weaker cells.  I believe that by continually monitoring SOC and occasionally charging to full every so often with an external battery charger, one can determine whether the battery is being undercharged.  My guess would be that if normal SOC from driving is less than around 80% of the maximum SOC after charging on an external charger, the battery is being undercharged.  If it is being undercharged, resetting battery age should likely help to maintain a better charging regime and should extend battery life.   From my recent observations, I recently reset my battery age (April 5th 2020) and also put my 5 year old battery on a charger until the charger indicates the battery is fully charged.  My SOC maxed out in the lower 60% (IIRC 63%).  After  about 7 weeks of normal driving since April 5th, my SOC today is 54%.

 

 

Edited May 27, 2020 by Plus 3 Golfer
correcting and clarifying my thoughts in 6 and 7

[Lacienega]

What happens when you disconnect your battery for 20 minutes? Will this automatically reset my battery age?

[takingittothemax]

12 hours ago, Lacienega said:

What happens when you disconnect your battery for 20 minutes? Will this automatically reset my battery age?

 

I don't think so. You have to use Forscan and a OBD-II connector, or do an elaborate set of manoeuvres to reset it.

[plus 3 golfer]

The problem with going through the “elaborate set of maneuvers to reset it” is that there is no apparent feedback (that I saw) indicating that the battery age was reset after completing the procedure. One inadvertent “slip up” in the reset procedure and the age will not be reset.  So, as takingittothemax indicates you would want FORScan to reset it and to verify the age was reset.  I believe that battery age like, for example, the odometer reading would be saved in permanent memory and thus not lost if the battery was disconnected for a long period of time.