Charging at low temperature

Mitsubishi Outlander PHEV Forum

Help Support Mitsubishi Outlander PHEV Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

jshp

Member
Joined
Oct 30, 2018
Messages
5
There is an electric bike video on YouTube. He says that lithium batteries should not be charged at or below freezing point. I wonder how his effects the Outlander phev.
Does anyone have any thoughts?
 
Mitsubishi has this to say about charging at various low temperatures (US Owners manual):

2pjxoE4.png

p3-13

6GhHg7x.png

3-14

tDM2M1X.png

3-15
 
jshp said:
There is an electric bike video on YouTube. He says that lithium batteries should not be charged at or below freezing point. I wonder how his effects the Outlander phev.
Does anyone have any thoughts?

I'm charging the battery of my electric bikes indoor ...
And I'm not going biking when outside is freezing

So ... I don't see how somebody should be concern about this on a ebike ... but I guess people may have different usage pattern on bikes ...

About the PHEV ... I don't really get how cold temperature could damage a battery ... I see that the internal resistance of the battery will be very high, making very difficult to charge or discharge the battery ... so making very difficult to full charge the battery, and as well, having little power from the battery at very cold temperature, possible when temperature is very cold, there is not even enough power for start up the ICE (at -30C per the pages above) .. but I don't get how cold temperature could damage a battery

I have been driving and charging my PHEV with temperature up to -12C ... and I did not notice any issue ... I did not had problem on get the almost full power in EV mode (50kw), nor I did see a dramatic drop in EV range to prevent to warm up my car and have 22km of daily drive

As far as I know .. unless cold temperature could cause to overcharge the battery if the charging process does not get adapted (which I doubt Mitsubishi did not properly take care of) ... cold temperature don't damage the battery .. it is hot temperature which speed up the oxidation which cause less battery capacity and higher internal resistance.

I even know people which store Lithium Battery used for RC Airplane Models in a fridge , for better preserve them when not used for long time :geek:

Except lower power and slower charging time ... I don't see any issue with cold temperature and Lithium Battery ... but ... I'm open to learn something new in case ... but I would like to see the real chemical/physical reason behind it ...
 
Old subject, but replying anyway.. For most lithium batteries, charging below 0C is really a no-no. That's why for example Nissan Leaf includes a battery heater, which first heats the battery before charging. There's good scientific explanation here:

https://electronics.stackexchange.com/questions/263036/why-charging-li-ion-batteries-in-cold-temperatures-would-harm-them

There is another thread on Outlander's battery A/C cooling system:

http://www.myoutlanderphev.com/forum/viewtopic.php?f=10&t=3491

Is it possible that in cold weather the A/C is simply reversed so it heats instead of cooling? Has anyone heard the blower going on at winter when charging?
 
Strange scientific explanation.

Also ... why freezing is consider 0C .. this is the freezing point of pure water ... in liquid inside the Lithium battery I doubt it get frozen just below 0C .. it must have a freezing point way below 0C

I also don't get why discharge up to -20C is not an issue , since the chemical process is just the reverse of charging ...

Anyhow ... I did check my DOG cards ... the coldest temperature from my pack has been -2C but for a single cell , probably when outside was around -10C

Per the article, just a single charge below 0 can cause immediately to lose a lot of battery capacity, and it is suggested to dispose the battery due to the high risk of potential explosion

Anyhow .... just find out the specs of our battery ... just for remove a legend:

Our battery have been rated to be able to handle charge up to -25C ... so ... this explain why the heater in the PHEV has been added on in some market

The BMU is well aware of this .. so ... I believe the PHEV knows well when and how to charge and discharge our 12kwh battery

GS-Yuasa-LEV50N-data-sheet.jpg
 
Ah, it's true that "freezing point" probably is not 0C. Also Mitsu says (above images) that charging at low temperatures can be slower. So maybe BMU indeed slows down the charging, to make it safe. And probably the battery heats a bit while charging, which allows for higher current later.
 
Zuikkis said:
Ah, it's true that "freezing point" probably is not 0C. Also Mitsu says (above images) that charging at low temperatures can be slower. So maybe BMU indeed slows down the charging, to make it safe. And probably the battery heats a bit while charging, which allows for higher current later.

Per the battery specs, it is allowed to charge up to 10A (0.2C) at -25 deg ... 0.2C is equal to 2.4kw charging for a 12kwh battery ... so ... actually even at -25C, we can normally charge our PHEV with the included charger (but I bet the process is slow down, or maybe even stopped at -25C for get extra safety compared to the battery producer specs)

Anyhow ... per the battery producer we are fine up to -25C

Per my experience the lowest battery temperature in my PHEV has been -2C .. with an outside temperature of -10C ... so there is still a gap between outside temperature and battery temperature .. this is why the active battery heater is included only in some special market only (Canada, Norway, etc)
 
elm70 said:
Per my experience the lowest battery temperature in my PHEV has been -2C .. with an outside temperature of -10C ... so there is still a gap between outside temperature and battery temperature .. this is why the active battery heater is included only in some special market only (Canada, Norway, etc)

Well, I'm from Finland, so.. :) -30C is usual at least few days each winter, but most of the time it's warmer.

I don't yet have my PHEV, should arrive next Sunday. :) It's from Sweden, so might have the heater as well.
 
Zuikkis said:
elm70 said:
Per my experience the lowest battery temperature in my PHEV has been -2C .. with an outside temperature of -10C ... so there is still a gap between outside temperature and battery temperature .. this is why the active battery heater is included only in some special market only (Canada, Norway, etc)

Well, I'm from Finland, so.. :) -30C is usual at least few days each winter, but most of the time it's warmer.

I don't yet have my PHEV, should arrive next Sunday. :) It's from Sweden, so might have the heater as well.

Definitely ... make sure that has the heater included ...

With -30C outside still the battery should never go below -15C .. which is still well inside the specs of the battery

But better to be sure to get the PHEV version for the Nordic countries

I'm quite sure my PHEV originally from Netherlands, does not have any battery heater ...
 
With or without the battery heater, the BMU will not attempt to charge the cells if it thinks it's too cold. Once you've driven on petrol for a bit then the battery pack temperature may well start to rise from drawing power from the cells, and so it'll be able to charge them again (whether from the engine or from an external electricity supply).

So I wouldn't worry - most likely the worst is that you'll end up using a bit of petrol, and after all this is a petrol/electric hybrid not a pure EV so you would be expecting to use some petrol anyway.
 
I've experienced a few mornings when the temperature where below - 20°C.

The normal charging isn't affected but regenerative braking is almost nothing - like when the battery is full. The car also goes into a mode where it's idling without any charging when there's no demand for traction power.

The manual is near incomprehensible in the section about what happens at -28°, but it looks like that charging is disabled, and possibly even driving if the battery temperature is -30°C, but it there is a section that could be interpreted as that connecting the charger may heat up the battery - presumably with the powered on - but who can tell.

On the other hand I've been stuck once or twice before in my old cars when the 12 v battery had run out of juice during a -25°C cold night, and diesel starts to fog up at some point below - 30°C.
 
Zuikkis said:
I don't yet have my PHEV, should arrive next Sunday. :) It's from Sweden, so might have the heater as well.


I am from Finland too. As far as I know, only 2019 models are equipped with battery heater in Finland. I guess Sweden models are most likely same.
 
-30C today, my second day of PHEV driving. :) It did charge normally during the night, I have charge timer starting at 00:00 because night electricity is cheaper.

But I also noticed that during driving, regenerative braking was almost non-existant, and ICE was running idle the whole time even if I was standing still and tried turning AC to +15C or completely off.. I decided that it's time to try EV driving some other day, heat back to +22C. :)
 
Zuikkis said:
-30C today, my second day of PHEV driving. :) It did charge normally during the night, I have charge timer starting at 00:00 because night electricity is cheaper.

But I also noticed that during driving, regenerative braking was almost non-existant, and ICE was running idle the whole time even if I was standing still and tried turning AC to +15C or completely off.. I decided that it's time to try EV driving some other day, heat back to +22C. :)

I did not monitor the charging process with extreme cold temperature

What I did notice is that the charging process at the end is way slower when outside temperature and battery temperature is just below zero (-2 battery temperature, -8 outside temperature) .. the end charging process that is ending in 30min/45min in summer time .. I did see it to last over 2h

Anyhow .. per the battery producer specs, these Lithium battery can be charged with reduced power even at -25C

While driving for over 200km ... with -5C outside .. my battery did jump from -1C to +28C ... so .. based on the usage even when outside is -30C ... I don't expect the battery pack going much below -15C

PS: For use regenerate brake, it is needed that battery is below 90% SOC, and as well, battery temperature is above 0 .. else the regen power is automatically limited by the "BMU"

PPS: How much our battery suffers at these low temperature ... we will see with the speed of battery degradation ... so far we have seen fast battery degradation from people in Australia , so in hot climate ... but ... I'm not sure if there is any evidence that PHEV from Norway, Sweeden and Finland will get faster battery degradation.
 
Back
Top