Is there is a way to find remaining capacity of Li-Ion battery

[dmk2000]

Hi everyone.

We just purchased 2013 c max SEL 301a (leftover).

When we picked up car, it had 9 miles on it, looks like factory original.

The reason we got this car, is because it was leftover form 2013 and in my area C max's do not move from the dealer lot so had room for negotiations.

Long story short, it was sitting on a dealer lot for about 11 month. Said that, Li-Ion batteries are very sensitive to been left discharged. What I understand, if Li-Ion battery left discharged for a long time, it will loose large chunk of charge capacity.

So the question is, is there is a way to see what is a remaining battery capacity is?

Thanks,

 

P.S. so far we got 150 miles on this car, and averaging 48 miles per gallon. same commute in Mazda 5 (traded it for C Max) was returning around 20. Therefore as far as performance, no complains.

[komondor]

I just picked up mine that was on the lot for a long time and I have had no issues at all, I think it has a April 2013 build date.

[dmk2000]

Thanks komondor.

Mine was build end of may 2013.

My concern is not build date but how well dealer kept this car. if they start them once per month to recharge batteries, then no problem. If they neglected these cars, than battery could be damage for been left in discharges state for too long.

Just want to see if I can run any internal test to see what battery internal capacity now.

[kostby]

Welcome!

 

The iithium ion batteries in our hybrid seems to have no problems sitting for a long time. (April 2013 production, purchased March 2014)

Same for my lithium-ion power tools that easily hold up to an 80% charge (and 100% apparent capacity) when left for months without being used.

 

It's the 12-volt lead-acid batteries that may lose the capacity to hold a charge over time.

You have a 2013 SEL, and those have very few reported 12-v battery problems anyway. 

It was primarily the SE's with either Equipment Group 200A or 201A that have suffered the most 12-volt problems, as reported in these forums.

[Adrian_L]

Technically speaking........you don't want to run them empty (like in a rechargeable drill) and then leave them empty.  But since the C-max's charging/discharging is very conservative you're probably fine.  The Lithium/Ion batteries do not drain their charge like regular 12 volt lead batteries as Kostby pointed out.

[fotomoto]

This battery chemistry doesn't like being left 100% charged in the heat or completely discharged for long periods of time.  But here's the rub:  Ford only uses the "middle" part of the battery.  IOW, when you see a full or empty indicator on the dash, it's neither.  Full is really closer to 80% of actual capacity and empty is around 20%.  It may be closer to a 75/25 ratio, I forget.   Another example:  my Energi model has a 7.6kWh battery but we only use 5.7kWh before running out EV miles and going into hybrid mode.  

[Adrian_L]

How I covet that beefy Energi battery..........

[plus 3 golfer]

To answer your question, I've not seen any write up as to how one can determine the maximum HVB capacity. I would think one would have to have the capability to charge the HVB to 100%. I would think that Ford should be able to do this or at least have an algorithm that estimates full HVB capacity.  But the Hybrid HVB is operated in a range well below 100%.  So, the HVB should never have a 100% charge on it and thus would not be subject to degradation from high operating temperatures and high charge.  

 

As far as discharging of the HVB over time to below minimum because the car is not driven in over 30 days, the owner's manual clearly states "Start the engine every 15 days. Run at fast idle until it reaches normal operating temperature."  There is no mention of any HVB requirements when storing the vehicle for mote than 30 days.  The dealer should be following this which should keep the HVB sufficiently charged yet adding little miles to the odometer as ICE will run if the HVB ever gets too low.

 

There are a few members that have monitored state of charge (SOC) of the HVB in the Hybrid (not the same as displayed on the battery gauge).   I have recorded SOC many times and never have seen SOC above 70% nor lower than about 30%.   So the usable capacity of the Hybrid HVB appears to be around 40% of 1.4 kWh or about 0.56 kWh.  However,  the typical operating range that I observe when driving is between about 40% and 56%. One can get in the low 30% in EV+ mode if  the battery level starts at a low level.and one can watch Empower and gradually reduce load by slowing down to keep EV power under the engine on threshold drops as it and SOC drop.   It's easy to reach the maximum of 70% when the normal SOC is high and one coasts / brakes from higher speeds to a stop or by going down a longer hill at virtually any starting SOC..

 

Here's a link to Ford's testing of the HVB.   

Edited July 24, 2014 by Plus 3 Golfer

[dmk2000]

Thank you every one for replying to my inquiry.

Igess I learned a great deal of information about HVB.

I see what ford did with HVB. Not like Tesla, where they can go as low as 5% of remaining charge.

Well, so far so good. In 2 days my wife drove 200 miles mixed driving, bunch of rolling hills, car still return 46 miles/gallon. Looks like HVB is good.

Thank you again.

 

P.S. first time Ford owner. (Prefer Japanese iron).

[plus 3 golfer]

Thank you every one for replying to my inquiry.

Igess I learned a great deal of information about HVB.

I see what ford did with HVB. Not like Tesla, where they can go as low as 5% of remaining charge.

Well, so far so good. In 2 days my wife drove 200 miles mixed driving, bunch of rolling hills, car still return 46 miles/gallon. Looks like HVB is good.

Thank you again.

 

P.S. first time Ford owner. (Prefer Japanese iron).

I think you have to look at the expected charge / discharge cycles in determining an appropriate operating SOC range assuming one wants a long battery life..  The larger the battery capacity, the more you should be able to extend the SOC range and not shorten the battery life.  The C-Max Hybrid battery which is 1.4 kWh might cycle around its normal SOC range say 30 times in 100 miles.  A Tesla battery won't cycle one time in 100 miles. Number of cycles, temperature, SOC cycle range will affect battery life.  So, a larger battery should be able to have a deeper cycle than a smaller battery and both should have about the same life since the larger battery cycles less.

 

I believe the NRG 7,6 kWh Battery should have a larger %SOC range than the 1.4 kWh Hybrid battery.  Someone with and Energi and ELM327 and OBDII App should be able to monitor the PID for the state of charge.  It wouldn't surprise me if the Energi SOC range might be 80+% down to 20% or less.

 

fotomoto, does the 5.7 kWh include the Hybrid operating portion of the NRG battery in EV mode  or does the NRG switch from all EV to Hybrid mode at say 70% of 1.4 kWh or 0.98 kWh remaining capacity - the upper usable limit of the Hybrid battery or at the lower end of the usable range?

Edited July 25, 2014 by Plus 3 Golfer