Battery drops to 70% in a couple of days... normal?

[makkaboo]

Hi,

Sorry for a newbie question but I couldn't find a thread with the same question!

I bought a 2014 Outlander PHEV with 35000 miles on it two weeks ago. Everything works fine, except one little detail: If I charge the battery to full, and leave it in the driveway for three days, the battery is not full when I want to use it but rather it's 70% charged. Is this normal? I don't drive every day, usually 1-2 times a week, and I don't really want to plan the charging ahead. I'd like to be able to charge it when I come back with an empty battery and then use it whenever I need it, no matter if it's one day or one week later. I saw a youtube video about the battery charging the 12V battery at 2pm every day, automatically. Could that be related to my problem?

Thanks in advance!

/Magnus

 

[jaapv]

That is so little, charging the 12V battery can never use such an amount. I would say 30% in 3 days is quite abnormal. Have it checked out.

 

[zzcoopej]

If I charge the battery to full, and leave it in the driveway for three days, the battery is not full when I want to use it but rather it's 70% charged. Is this normal?

No, that's not normal, you should lose only 1-4% (and some of that is from a >100% starting point which our internal analysis of the PHEV CAN bus has uncovered).
I'd put money on there being a heating or cooling timer set by the previous owner. Another forum owner discovered the same issue a while back IIRC.

 

[elm70]

Hi,

Sorry for a newbie question but I couldn't find a thread with the same question!

I bought a 2014 Outlander PHEV with 35000 miles on it two weeks ago. Everything works fine, except one little detail: If I charge the battery to full, and leave it in the driveway for three days, the battery is not full when I want to use it but rather it's 70% charged. Is this normal? I don't drive every day, usually 1-2 times a week, and I don't really want to plan the charging ahead. I'd like to be able to charge it when I come back with an empty battery and then use it whenever I need it, no matter if it's one day or one week later. I saw a youtube video about the battery charging the 12V battery at 2pm every day, automatically. Could that be related to my problem?

Thanks in advance!

/Magnus

Leaving the car fully charged for days it is a very bad practice .. you will cause to de-gradate very fast your main battery

Since your car is new for you ... double check if there is any programmed climate control on daily base ... if there is a daily activity for heat up the car for 10 or 20 minutes, this can explain the lost of battery energy

If your car has Wifi module and you are not using and/or you don't have the password .. you should better follow the procedure for disable the WiFi .. also disable and re-enable the wifi module is a good practice for reset all the WiFi module setting and allowed device that can connect to the PHEV

 

[makkaboo]

No, that's not normal, you should lose only 1-4% (and some of that is from a >100% starting point which our internal analysis of the PHEV CAN bus has uncovered).
I'd put money on there being a heating or cooling timer set by the previous owner. Another forum owner discovered the same issue a while back IIRC.

Bingo! I found a pre-heating schedule that I wasn't aware of, and switched it off. Now I'll just have to see if the battery has (close to) 100% left tomorrow morning!

 

[makkaboo]

Leaving the car fully charged for days it is a very bad practice .. you will cause to de-gradate very fast your main battery

Is this a known fact, that it's better to charge it just before you're going to use it?

 

[zzcoopej]

Leaving the car fully charged for days it is a very bad practice .. you will cause to de-gradate very fast your main battery

Is this a known fact, that it's better to charge it just before you're going to use it?

Yes its a known fact that Lithium are most happy at about 50% SOC. However I have owned a PHEV for over 2 years and regularly leave it 2-3 days after a full charge and haven't noticed any greater degradation than other owners (my PHEV is the red line on the chart below). We think leaving at full charge is not so bad because 100% on the dash is not really 100% in the battery due to an unused portion at the top and bottom of the battery SOC (State of Charge) range.

https://i.imgsafe.org/b6a9194228.png

If that doesn't work, here is an older version - http://evpositive.com/battery-history.html

 

[elm70]

Leaving the car fully charged for days it is a very bad practice .. you will cause to de-gradate very fast your main battery

Is this a known fact, that it's better to charge it just before you're going to use it?

Lithium batteries are well know to have a "ageing" effect.

When they are fully charged they have a faster oxidation process, which cause higher internal resistance and less capacity

This is very evident on Laptop battery .. normally after 3 years they are dead .. since 99% of the time they are left fully charged.

If you seldom use the PHEV, and leave the car all time ready to drive, it means it will be sitting most of the time with the battery fully charged, so at a faster de-gradation rate.

I'm using daily my PHEV, but still I program my charger to start charging from midnight, for have the car fully charged only for few "minutes" before I start my usage .. and if in the weekend I don't have plan to use the PHEV I don't charge it

My "old" PHEV was used by a guy who did not bother to ever charge the car, and as result, my PHEV battery condition is sensible better then what people report here for a similar age PHEV

On the other side ... people that have apparently quite de-gradated battery are still reporting to be able drive over 40km in EV mode, that is similar to my PHEV (but I may have a more heady right foot when driving) .. so maybe battery degradation does not really impact much on efficient usage of this PHEV

As well, the PHEV does not ever fully charge the battery nor does get close to fully discharge them ... still if charged and unused, the Lithium cells are left in the PHEV at 4.1v ... vs an ideal storage voltage that is around 3.80/3.85v .. in theory max voltage on a Lithium cell is 4.20v ... in some cases it is even pushed up to 4.30v when life of the battery is less relevant then the energy requested (like on the latest drones which care to a advertise a long flight time and don't care much if the battery life is reduced to only few hundreds of "cycle" vs one thousand )

 

[elm70]

Yes its a known fact that Lithium are most happy at about 50% SOC. However I have owned a PHEV for over 2 years and regularly leave it 2-3 days after a full charge and haven't noticed any greater degradation than other owners (my PHEV is the red line on the chart below). We think leaving at full charge is not so bad because 100% on the dash is not really 100% in the battery due to an unused portion at the top and bottom of the battery SOC (State of Charge) range.

https://i.imgsafe.org/b6a9194228.png

If that doesn't work, here is an older version - http://evpositive.com/battery-history.html

My PHEV has 35.7Ah capacity after 126k km from Dec '13 ... so it is doing way better then average .. thanks to the previous owner that used the PHEV like a normal ICE car

I expect many PHEV owners are charging their PHEV, and leave the car for an high amount of time fully charged .. and as result .. it is "looking normal" the battery degradation on the PHEV

 

[makkaboo]

Thanks everyone for your helpful tips! First, I want to make sure that the battery actually isn't faulty i.e. that it will in fact have close to 100% capacity tomorrow morning (now that I switched off the scheduled preheating).

My most common trip is about 10-15 miles (two-way) which means I can make that trip on around 50% of a charge. So I'll probably try to charge it to full only for longer trips, otherwise try to keep it at 50-75%.

 

[elm70]

Thanks everyone for your helpful tips! First, I want to make sure that the battery actually isn't faulty i.e. that it will in fact have close to 100% capacity tomorrow morning (now that I switched off the scheduled preheating).

My most common trip is about 10-15 miles (two-way) which means I can make that trip on around 50% of a charge. So I'll probably try to charge it to full only for longer trips, otherwise try to keep it at 50-75%.

Make two trips of 10/15miles without an additional charge or using ICE can be not trivial ... almost impossible in winter

But .. charge 1h before the 2nd trip should allow to have enough battery for make the next trip in full EV mode.

It would be nice if the PHEV could have a function to decide up to which level should be charged , since charge the car up to xx% does need some "extra care"

Anyhow .. I'm sure you will find out the best way to use your PHEV ... also you may want to consider to get EvBatMon application with a proper ODB2 adapter, so you can better check the status of your PHEV and also better understand how does it works.

PS: I'm quite sure your PHEV does not have any issue on keeping the battery capacity ... only damaged Lithium battery develop a self discharge ... that means you would have an extremely low range in EV mode plus some possible error on the dash ... as well ... so far nobody here reported a damaged battery pack in this PHEV

 

[makkaboo]

If anyone is interested, the previous owner had a daily heater schedule, which was causing my problem. The schedule is removed, and the battery has 100% even after a few days. Thanks everyone for your comments and tips!