Does Mini discourage frequent charging?

[JoeC]

Does Mini provide any recommendation on how frequently to charge the car, when you have the flexibility? Let's say you drive 20 miles a day and can get 4-5 days worth of driving out of a single full'ish charge. In that case, do they recommend topping up the charge every night or is it better to let the battery get closer to 0% and then do one big overnight charge to get back to near/full? I have heard that the fewer fast/super charges the better (e.g., for Tesla), but I am not sure if this matters for slow charging.

This will influence whether I need to invest in a Level 2 charger. If I simply top off every night it will be easy to get by with only a Level 1 charger which can easily add 20+ miles a night. If more frequent charging is discouraged, then I might need a Level 2 charger to ensure that I can get from 10% or so to 80-100% overnight when I charge every 4-5 days.

Thanks for the assistance!

 

[ColdCase]

I've read here that Mini doesn't care. The car will protect the batteries regardless. I plug mine in about every time I drive it. Leave it plugged in for long periods. I never know when I will need a full battery for a longer trip. Tesla is much different, they seem to depend on the owners to be nice to their batteries.

 

[JoeC]

I found an Owner's Manual online and it advised the following: "In order to operate the high-voltage battery optimally, charge the vehicle regularly and fully using a compatible charger" (p. 218)

 

[Greencarguy]

Batteries in general degrade faster if overheated, which would only really be an issue with DC fast charging or really pushing the car. The BMS should know this and slow the charge speed as needed or limit torque output, which mini does. It is better to charge it frequently than it would be to leave it too low for extended periods. I kind of wish the mini let us set an 80% charge limit. Judging by others results in fast charging (staying at 50kw as the battery neared 90%soc) it’s safe to say that BMW has put a healthy buffer in it. I would just charge it frequently and enjoy your car.

 

[insightman]

I've read here that Mini doesn't care. The car will protect the batteries regardless. I plug mine in about every time I drive it. Leave it plugged in for long periods. I never know when I will need a full battery for a longer trip. Tesla is much different, they seem to depend on the owners to be nice to their batteries.

Here's my take on MINI's no-worry charging regimen: MINI realized that a car with 110/114-mile range per charge is going to be charged often and always charged fully. One of the few cautions about charging in the Owners Manual is to make sure to fully charge the battery before putting the SE into storage because allowing the battery to fully discharge can result in a failure:
Before storing the vehicle for an extended period, ensure that the high voltage battery is fully charged.

The company could have given the SE greater range with the same battery by reducing the size of the bottom-end and top-end battery buffers. Maybe 20-25 miles greater range. Then MINI would have had to direct owners to observe a set of charging rules to maximize the service life of the battery the way Tesla does. However, the SE would still be a short-range EV and some owners would ignore the charge-with-moderation advice, their batteries would suffer early failures (right after the warranty expired) and the SE would get a bad reputation.

MINI decided it was better to sacrifice the greatest possible range such a small battery could deliver and make the battery able to accommodate frequent charging to a fully charged state without suffering ill effects. Just like MINI claims the SE takes 6.9 seconds to get to 60 mph, they understate the SE's maximum range to ensure owners would not be disappointed. As many owners have pointed out, the SE is easily able to surpass the nominal 110/114-mile range specification.

 

[Puppethead]

Then MINI would have had to direct owners to observe a set of charging rules to maximize the service life of the battery the way Tesla does.

Sadly, this has become baked into everyone's perception of BEVs when it's clearly manufacturer-specific. I prefer MINI's approach of KISS (Keep It Simple, Stupid). This recent article, 6 ways electric car drivers can save money on home charging, perpetuates the misconception, with no regard to model, that a driver has to manage the battery percent.

For MINI it's ABC - Always Be Charging.

 

[JoeC]

Thanks. There are a few different issues here, potentially only tangentially related. You are discussing why Mini built in a buffer and whether it is OK to charge up to the buffer (or stop at 80% of buffer).

My question was more around does the # of charges have an impact on battery health. Mini's recommendation to top off every night suggests that # of charges doesn't impact battery longevity. Tesla also recommends nightly top off, even though their larger batteries mean that many drivers don't need to do this to satisfy their driving habits.

I think my and others' worry about frequent charging comes from other battery products which have a memory effect and benefit from more thorough battery depletion and less frequent charging (as opposed to frequent retopping). (It looks like this effect doesn't impair lithium batteries, however.) Also, warnings against Tesla owners frequent SuperCharging made me concerned about frequent charging at home, but this is a totally different thing - it's more about SuperCharging than frequency of charging.

Thus, it sounds like the recommended approach (potentially on all EVs) is to plug it in every night. This is good as it means I might be able to get away with a Level I setup. Also means that I will have 100 miles of range available most days just in case.

Thanks again for all of the input!

 

[Puppethead]

My question was more around does the # of charges have an impact on battery health.

When I picked up my SE I asked the dealer about this, and was told to charge as often as I wanted, even fast charging. Since the maximum draw the SE will take is 50 kW, there's no worry about overheating during the charge process.

 

[Jim In Tucson]

As the Leaf and Prius have so clearly not demonstrated, I think the key to long battery life is simply good thermal management.

Blowing a small stream of air on the battery with a small fan is NOT good thermal management.



Sent from my iPhone using Inside EVs

 

[polyphonic]

In addition recommending the car be plugged in and fully charged as often as possible, the manual even warns to "not allow the vehicle to sit idle for longer than four weeks with a charge state below approx. 80%."

This last bit about 80% is counter to much of what I have read about batteries (Battery University), and most of the other EV manuals. Some manuals suggest storing their cars around half charge. Not Mini.

While the Mini has a top buffer, it's around 8% IIRC. So 100% = 92%. They must have a different battery management scheme in place than most other EVs.

Like other replies aid, KISS and ABC. But if that's too hard, IDGAF also works! You'll be fine either way.

 

[F14Scott]

In the larger Tesla universe, there are a ton of people who really get into the battery science. From them, I gather:

1. The closer a battery rests to 50% full, the better.
2. Fewer charging cycles is better.
3. DC charging is worse.
4. Fastidious adherence to 1-3 might mean a percent or two less degradation than normal, over 200,000 miles.

In the Tesla, we charge it to 80% and then let it run down to about 100 miles (30ish percent) before plugging in, simply because we have no need to charge very often.

In the MINI, I charge every time I pull in.

 

[bldxyz]

I charge when I want to, not every night.

I usually wait until it is under 50% to plug in, not for any reason of battery performance or future degradation, but for convenience.

We rarely need 100 miles. We have a first in, first out garage and the charger is on the opposite wall from the port on the Mini. (It just couldn’t be on the other side since there is not a wall on that side). Plugging it in isn’t super inconvenient, but it is not super easy either.

 

[Aprime]

I've read here that Mini doesn't care. The car will protect the batteries regardless. I plug mine in about every time I drive it. Leave it plugged in for long periods. I never know when I will need a full battery for a longer trip. Tesla is much different, they seem to depend on the owners to be nice to their batteries.

I hate to bump this, but the manual states to keep the battery between 10-80%SOC for regular (so as to extend battery life) use and 30-50% for storage. There's nothing about the BMS handling this and the omission of user SOC management is disappointing. Confidently wrong is how I'd describe everything I've found online about this, because the only official info is in the owner's manual, which you all should be reading.

The whole "nominal vs usable" battery thing is common across EVs, and for all the comparisons to the i3, the batteries for it weren't made by CATL, so we can't expect and direct translation of the reliability or longevity, we can just hope the car meets the currently established BMW EV standard.

It's like all the talk about preconditioning where no one knows if any heat is used to warm up the pack or it's all just for the cabin, which yeah, that saves initial and substantial draw, but preconditioning doesn't mean the same thing across automakers right now... And per the manual, in this car, it's limited to the cabin.

As far as expectations for longevity, stand by the definition of a charge cycle and find out what the pack is rated for.

 

[revorg]

Wait, I'm confused. You say that the manual says that preheating is limited to the cabin, but your attached png says to bring the high voltage battery to operating temps by preconditioning.

 

[Aprime]

As I understand it, precon while connected doesn't bypass the battery, but I don't think (separate loops) the cooling system is connected to the battery. The precon section doesn't mention the battery getting conditioned so that's a good catch, but it's definitely unclear and confusing. I'm not done reading, ironically, but the charge management bit stuck out because every time I googled limiting, everyone was saying "just charge to 100", when the manual is explicit in stating you should be managing the charge to extend the life of the battery, but provides no means of doing so besides playing with scheduling.

I think the warranty term speaks to the expected lifespan of our car. ICE minis have had an unfortunately disposable design (maintenance difficulties stemming from design choices) in the past and it's definitely been a concern when I bought this car. I'm just hoping we get a continuing of the i3 experience.

 

[Quiet Mini]

The manual states “At high temperatures, the high-voltage battery is initially cooled. There may be a delay before charging starts.” and “Do not allow the vehicle to sit idle for longer than four weeks with a charge state below approx. 80 %.” Is the manual different on newer ones?

https://www.miniusa.com/content/dam...NI_Owners_Manual_F56_Cooper_SE_SOP_3-2022.pdf

 

[insightman]

I'm glad I bought my SE back in 2020, before MINI started installing batteries that failed earlier if you charged them to more than 80%. I thought the 110-mile range was just enough--88 miles wouldn't be enough.

I'd love to learn what level of MINI executives were involved in that change to the Owners Manual and how the decision was made. If MINI had changed the BMS to provide 137.5 miles of EPA range and then suggested owners should charge to 80% (110 miles range), it would all make sense to me. But I would have expected MINI to provide a BMS with an 80% charging option.

MINI certainly knew that a car that offers only 110 (or 114) miles of range would be charged fully every time. So I assumed the BMS was designed to prevent battery degradation caused by full-charging. MINI has my home address, but didn't send me an updated Owners Manual or an bulletin explaining the new 80% suggestion.

Does BMW tell customers of their BEVs to charge to 80% unless they need the full range?

It could be worse: Toyota decided owners of their bz4x BEV crossover can use DC fast-charging only 2 times in 24 hours!

A trip that takes 9 hours with a gas car took me 23 hours.

 

[fishbert]

ICE minis have had an unfortunately disposable design (maintenance difficulties stemming from design choices) in the past and it's definitely been a concern when I bought this car.

What are you referring to? I've had an R56 Cooper S and a F56 Cooper S, and I'm not sure what "maintenance difficulties stemming from design choices" you're alluding to. The only thing that comes to mind is the carbon buildup issues with the R56S, but that wasn't a MINI-specific thing by any stretch [Ford, Audi/VW, Hyundai/Kia, etc.].

 

[Aprime]

I'm using the motorer's guide that's in the app in Canada for my screenshots, it's a virtual version of the manual for my car. I drive a '23.

Another thing is we have to be cognisant of unreported changes across model years/mid model years. Not everything that changes goes on to be reported on forums or in media/by the make'scPR, and even when it does, it's not even necessarily accurately. The video we did on the SE has a fair bit of incorrect info, for instance. Ultimately accurate information comes directly from the documentation on your specific vehicle.

The battery is actively cooled, that's not into question (and it's why we can supposedly expect better longevity vs a Leaf), it just doesn't seem like preconditioning does anything to the battery.

 

[Aprime]

What are you referring to? I've had an R56 Cooper S and a F56 Cooper S, and I'm not sure what "maintenance difficulties stemming from design choices" you're alluding to. The only thing that comes to mind is the carbon buildup issues with the R56S, but that wasn't a MINI-specific thing by any stretch [Ford, Audi/VW, Hyundai/Kia, etc.].

Haha don't take it too personally, the cars have a reputation for poor reliability and relatively high maintenance costs. It's nothing new. Owners used to rank service quality highly but conversely the cars were at the bottom of the list for reliability, and consistently so. Tesla is another paradox here in that they have an insane amount of repeat buying (for now), but are plagued by service complaints and quality concerns.

For Mini it was mostly powertrain stuff. Turbos, timing chains, all big ticket stuff.
Nobody's saying they're unique to Mini either, and yeah, the F56 might be better than its predecessor. Heck, there's plenty of minis in my neighbourhood from both generations. Ultimately, my car's a mix of old and new and I don't know what to expect. So far just judging from people's ownership experience, it's looking good, but the CATL prismatic battery we have is a mystery.