I got my XC40 P8 in April and really enjoy it. To be nice to my battery I would like to know if limiting the charging current on the central display while charging, would increase the life of the battery. I normally charge twice a week with a wallbox in my garage to a limit of 80%, rarely to 90 or 100%. Time is no factor even if I limit the charging current to 10 or 12 amps. I haven't found any informations on this subject in the Volvo documents.
Limiting the Charge Current
1 - 9 of 9 Posts
I think using your standard home charger, it doesn’t charge super fast so it’s pretty easy on the batteries depending on what your home charger’s output is. If you have the time, then yes, by all means set your charger to 10 amps. The DC fast chargers (up to 150 kW on the XC40) are harder on the batteries, so only using them for longer trip or when a quick charger is required will help preserve your battery’s health. One of the reasons fast charging is harder on the batteries is it generates a lot more heat than slow charging.
Joined
·
2,195 Posts
I remember reading something a good while ago about fast vs slow charge and battery life.
Alas margo lives on high speed charging. I am curious as to how this is shortening her battery life.
Do you have any links Greg S or anyone. Seen lots on how the max soc level but not much on fast vs slow.
Cheers
OK, we were able to dig up some specifics of the XC40 battery pack and modules. If you want more detail check out this article (Let's Take A Closer Look At Polestar 2 Battery Details) that describes the Polestar 2 pack - same as the XC40. Based on the battery pack voltage (400V), the pack capacity (78 kW-h) and the “3p” configuration, we can calculate that each battery has a 65 amp-hour capacity...that amp-hour figure is what’s called the “C” rating of a battery...the constant current the battery will produce for a period of 1 hour taking it from 100% to 0%. With lithium batteries, typically the slower you charge or discharge them, the longer they last. The battery manufacturer usually specifies a maximum continuous charge and discharge current, and often times also a peak discharge current (for a duration - for example 10 seconds). This rating is expressed as a ratio of the battery C rating...so they may say max (for example) continuous charge/discharge current is 2C, which in the case of the Volvo would be 2x65=130 amps. We don’t really know the Volvo (LG Chem) battery max charge/discharge ratings. What we do know is if you’re charging at 150 kW (max DC fast charging) that would equate to 150kW/400V=375 amps...and if we know the battery modules are 65 amp-hours, then charging at the max 150 kW would mean 375/65 = 5.8C...from what I’ve read, that’s pretty high. Most lithium batteries I think they recommend charging a .5-1C continuous charge/discharge current...which in the Volvo’s case (use 1C) would be 1x65x400=26kW DC...anyways, it’s a bit of speculation, but I think if you can charge at 25 kW DC for regular charging, and only use the 150 kW DC chargers for your long trips, your battery will thank you. Given proper heat management, you would hope they have designed the batteries to last for the 8-year warranty period with minimal degradation, but it’s anyone’s guess how these will last with a lot of rapid charging. Sorry all of that may be a bit too technical and a bit vague, but there’s a lot more info out there and I just some some fairly generic numbers...we don’t really know what the comfort limits are on these batteries but suffice to say, the less often you use super high charge rates, the better it will be for the batteries.
Joined
·
2,195 Posts
Thanks for the info 
sad face because I have no charging choice for now. Condo has no charging stations so I charge out in the wilds of the city.
Information is good even if it is not good news more motivation to get a house. We almost did before Covid hit. Such is life. #firstworldproblems.
Thanks
sad face because I have no charging choice for now. Condo has no charging stations so I charge out in the wilds of the city. Information is good even if it is not good news
more motivation to get a house. We almost did before Covid hit. Such is life. #firstworldproblems. Thanks
I wouldn’t worry TOO much about it, but if you’re not in a hurry, maybe use a 50 kW charger instead of an ultra-fast one that charges at the max rate of 150 kW. I know here in Australia we have some that are around 25 kW...but I guess it depends on your situation. Or, if you can set the charge limit ON THE CHARGER to be lower, you could try that, but I doubt that’s possible (guess it depends how sophisticated the charger app/software is).Thanks for the info
Information is good even if it is not good news
Thanks
Joined
·
2,195 Posts
Also with the soc curve it only actually charges at the higher rate when low.
I wonder if keeping it topped off would lead to a longer life on level 3s.
But it is what it is so not going to worry too much about it serenity and all
I wonder if keeping it topped off would lead to a longer life on level 3s.
But it is what it is so not going to worry too much about it
serenity and all
Yeah, don’t think it would make too much difference if you’re using the DC chargers...you’re right in that if the SOC is higher when you start charging, the rate will be lower due to the charge curve. Another option is to try and find a public (J1772 in USA) AC charger, but the max rate is 11 kW limited by the car’s onboard AC charger so it’s going to be SLOOOOW compared to the CCS DC chargers.Also with the soc curve it only actually charges at the higher rate when low.
I wonder if keeping it topped off would lead to a longer life on level 3s.
But it is what it is so not going to worry too much about it
Joined
·
2,195 Posts
A publicly 11kW would take too long I am happy with my living on edge risking it all charging at level 3s
I am happy with my living on edge risking it all charging at level 3s 1 - 9 of 9 Posts
Join the discussion
