BMW i3 REX - Taking too long to charge on Maximum Setting

[noakey]

Unfortunately the i3s are having onboard charger failures and it sounds like you have experienced it (as I did). The car has two 3.7kW chargers which combine for the ability to charge up to 7.4kW. On many cars, one of the chargers fail so the car will only charge at about 3.5kW max which is why your car is taking so long to charge. Here is my post from another thread about the issue:

Notice: Onboard charger replacement and temporary reduction of charge rate

Over in the i3 Facebook group there have been some discussion here regarding the charge rates of some cars that have been returned from service once they had a new onboard charger(KLE) installed. Some people have reported that their car is taking longer to charge than it did before they had the service. I now have the real facts on this from BMW NA and it will be officially communicated through them soon. I just wanted to get this out there now before anyone else wonders why their car may be charging slower after service.

Unfortunately the lower charge rate is indeed going to be the case, but it is only a temporary measure. The problem is some i3s (BEV and REx) are having a failure of their onboard charger and the result is the car will only charge at half the usual rate (roughly 3.5kW instead of around 7kW). BMW has identified the cause and is in the process of developing a permanent fix for this which I believe will be a new KLE. In the meantime, if your KLE fails and you bring it in for the service, they will install a new KLE(the same one as the one you have), and then reduce the charge rate by about 20% (you should see about a 5.8kW draw instead of the ~7kW draw the car can take now). This will help to prevent the new unit from failing again but it is only a temporary measure until the new, permanent unit can be installed. What this means is instead of charging at about 23 miles per hour, you'll be charging at about 18 miles per hour (of course, YMMV) and instead of a 3.5 hour full recharge, it will be about 4.5 hours.

I don't have any time official frame, but I expect this to be a short stint of perhaps a couple months, that's all. Many of you won't even be effected, as long as your KLE doesn't fail. One suggestion I have that will prevent any failure is to set your charge rate to minimum if you don't need to charge faster, like if you are recharging overnight. The lower charge rate will prevent the KLE from failing and you won't be inconvenienced by having to bring it in for service just yet. No, I realize it's not ideal, but BMW does indeed have a permanent fix and the cars will indeed have the 7.2kW charge rate we were promised. I'll update more as I get information on this.

I'm not sure if the European i3 owners have been experiencing the same onboard charger issues as we have been here in the US, but I'd like to hear about it if you have. I'm not sure exactly why it would only affect us here, but I do know the KLEs are failing at a pretty good rate and many of the i3 owners that I know have had the problem, including me.

The temporary charge rate does not effect level 1 charging or DCQC, just level 2 charging.

I'm starting to see this issue myself. We used to charge in 3.5 hrs and now at 4.5 hrs and today saw as high as 5.5 for a full charge. i also can't get fast charging to work, the car constantly has an error about "reduced" charging! and I'm constantly loosing communication with the car and the app.

I'm taking mine to the dealer and asking for a fix to all of it or my money back. The car has already stranded me twice.

How do you mean stranded?

 

[Boatguy]

In the meantime, I have learned that the standard Level 1 charger is somewhat "smart" and you will notice changes in the charge times dependant on how much power you are using overall in your house. I may plug it in and it says 9:20 AM and then 30 minutes later once we are ready for bed (and have turned off appliances) it will say 5:45AM. It regulates itself somehow.

While I appreciate the update on the fix for your i3, I'd like to suggest that the Level 1 charger is not smart enough to know how much current is available on a particular circuit at your house. In fact nothing in your house is actually that smart. Each circuit in your house can draw current until it exceeds the circuit breaker on that circuit (typically 15-20a for a 110v circuit), irrespective of what else is going on in the house (at least until you blow the main circuit breaker for the whole house).

Charging a battery is like pouring a glass of beer. Think of the heat in the battery like the foam (aka head) on the beer. Dump the beer in too fast, you get a lot of foam and can't fill up the glass with beer. You have to modify the pouring rate to keep the foam in check. When battery heats up, the charger slows the charging rate to keep the temperature in check. When the battery starts getting full, like pouring a glass of beer, you have to pour more slowly to top up the glass. When charging batteries, the last 20% can easily take as long as the first 80%.

When you see the time to full charge reduced, it is not because the battery is getting more current. It's more likely because the battery is drawing less current which tells the charging circuitry that battery has reached a certain state of charge (aka SOC) and it can correct the time estimate based on a better understanding of the state of the battery.

 

[noakey]

In the meantime, I have learned that the standard Level 1 charger is somewhat "smart" and you will notice changes in the charge times dependant on how much power you are using overall in your house. I may plug it in and it says 9:20 AM and then 30 minutes later once we are ready for bed (and have turned off appliances) it will say 5:45AM. It regulates itself somehow.

While I appreciate the update on the fix for your i3, I'd like to suggest that the Level 1 charger is not smart enough to know how much current is available on a particular circuit at your house. In fact nothing in your house is actually that smart. Each circuit in your house can draw current until it exceeds the circuit breaker on that circuit (typically 15-20a for a 110v circuit), irrespective of what else is going on in the house (at least until you blow the main circuit breaker for the whole house).

Charging a battery is like pouring a glass of beer. Think of the heat in the battery like the foam (aka head) on the beer. Dump the beer in too fast, you get a lot of foam and can't fill up the glass with beer. You have to modify the pouring rate to keep the foam in check. When battery heats up, the charger slows the charging rate to keep the temperature in check. When the battery starts getting full, like pouring a glass of beer, you have to pour more slowly to top up the glass. When charging batteries, the last 20% can easily take as long as the first 80%.

When you see the time to full charge reduced, it is not because the battery is getting more current. It's more likely because the battery is drawing less current which tells the charging circuitry that battery has reached a certain state of charge (aka SOC) and it can correct the time estimate based on a better understanding of the state of the battery.

Hey.. the analogy is perfect.. great explanation...

 

[M2140]

Unfortunately the i3s are having onboard charger failures and it sounds like you have experienced it (as I did). The car has two 3.7kW chargers which combine for the ability to charge up to 7.4kW. On many cars, one of the chargers fail so the car will only charge at about 3.5kW max which is why your car is taking so long to charge. Here is my post from another thread about the issue:

Notice: Onboard charger replacement and temporary reduction of charge rate

Over in the i3 Facebook group there have been some discussion here regarding the charge rates of some cars that have been returned from service once they had a new onboard charger(KLE) installed. Some people have reported that their car is taking longer to charge than it did before they had the service. I now have the real facts on this from BMW NA and it will be officially communicated through them soon. I just wanted to get this out there now before anyone else wonders why their car may be charging slower after service.

Unfortunately the lower charge rate is indeed going to be the case, but it is only a temporary measure. The problem is some i3s (BEV and REx) are having a failure of their onboard charger and the result is the car will only charge at half the usual rate (roughly 3.5kW instead of around 7kW). BMW has identified the cause and is in the process of developing a permanent fix for this which I believe will be a new KLE. In the meantime, if your KLE fails and you bring it in for the service, they will install a new KLE(the same one as the one you have), and then reduce the charge rate by about 20% (you should see about a 5.8kW draw instead of the ~7kW draw the car can take now). This will help to prevent the new unit from failing again but it is only a temporary measure until the new, permanent unit can be installed. What this means is instead of charging at about 23 miles per hour, you'll be charging at about 18 miles per hour (of course, YMMV) and instead of a 3.5 hour full recharge, it will be about 4.5 hours.

I don't have any time official frame, but I expect this to be a short stint of perhaps a couple months, that's all. Many of you won't even be effected, as long as your KLE doesn't fail. One suggestion I have that will prevent any failure is to set your charge rate to minimum if you don't need to charge faster, like if you are recharging overnight. The lower charge rate will prevent the KLE from failing and you won't be inconvenienced by having to bring it in for service just yet. No, I realize it's not ideal, but BMW does indeed have a permanent fix and the cars will indeed have the 7.2kW charge rate we were promised. I'll update more as I get information on this.

I'm not sure if the European i3 owners have been experiencing the same onboard charger issues as we have been here in the US, but I'd like to hear about it if you have. I'm not sure exactly why it would only affect us here, but I do know the KLEs are failing at a pretty good rate and many of the i3 owners that I know have had the problem, including me.

The temporary charge rate does not effect level 1 charging or DCQC, just level 2 charging.

I'm starting to see this issue myself. We used to charge in 3.5 hrs and now at 4.5 hrs and today saw as high as 5.5 for a full charge. i also can't get fast charging to work, the car constantly has an error about "reduced" charging! and I'm constantly loosing communication with the car and the app.

I'm taking mine to the dealer and asking for a fix to all of it or my money back. The car has already stranded me twice.

How do you mean stranded?

This past weekend we planned on trying out the quick charger and do some shopping in San Diego. There was no charge station at our intended location and we did not plan on staying any long than 2 hrs so the quick charge was our best bet to get home.

Quick charge failed, so we had to go find a regular charger to kill 3.5 hrs. Then we got a nice little surprise when we plugged in and the timer stated 6 hrs for a recharge. 6 hrs is a long time to kill at a crappy mall. I have a Rex but the drive home has a couple of nasty hills and we did not want to risk getting stuck going 25 mph up a hill on the freeway.

We ended up killing 3 hours at the mall for only half a charge. It got us part of the way home but the Rex got a check engine light on the hills so we stopped for an hour at another charge station to get just enough to make it home and past the hills.

The car is at the dealer now, been there for 3 days and they don't know what is wrong yet.

 

[i3cam]

Was it a Blink charger in San Diego ? Blink reduced the charging rate on all public chargers because of the connector overheating, then the company got bought out by car charging group and I'm not sure if this issue has been fixed yet

https://getsatisfaction.com/blink/topics/blink_network_charge_rate_on_j1772_30_a_or_less

 

[M2140]

Was it a Blink charger in San Diego ? Blink reduced the charging rate on all public chargers because of the connector overheating, then the company got bought out by car charging group and I'm not sure if this issue has been fixed yet

https://getsatisfaction.com/blink/topics/blink_network_charge_rate_on_j1772_30_a_or_less

The Level 2 station that said would take 6 hrs was a blink station. but I have plugged into blink stations before and never got a 6 hr recharge time. The car is now 5 days at the dealer, a 2nd software update, and the dealer is no closer ti finding out what is wrong. The dealer is honestly slow and completely clueless on how to fix the I3 and rely on BMW NA for how to troubleshoot the cars. Many times BMW NA takes days to reply because the last software update took 4 days.

 

[jadnashuanh]

This is my not fully informed idea of what is happening based on tidbits from various sources - may be wrong!

For the time being, at least in the USA, to fix an i3 via a software update, the dealer must connect with the servers at BMW headquarters and transfer a huge amount of data to reprogram the vehicle - IOW, the requisite code is customized for each vehicle's VIN and option complement. If there's a server glitch, it can take much longer than desired. With the number of i3's the dealers are trying to reprogram seems to be overloading the servers, causing dropouts and a slowdown, and possibly a requirement to restart. Those servers should have been adequate for 'normal' situations, but not when lots of vehicles are being addressed at the same time. This may also tie into the issues people are having with the remote control app - the servers are really busy. IT takes a bit to expand a network. While lots of BMW's have huge amounts of data in them, the i3, being somewhat unique, doesn't have all of the history of most other cars, so a few more glitches should be expected. I believe all of this will be sorted, but it will take a bit.

 

[noakey]

Email from bmw customer service..

"I have spoken to technical and the current charge rate is due to the new software that was applied to your car. This was applied to all i3’s and all current i3’s, as it helped to stabilise the charging process. This was implemented to stop the potential failure of additional parts due to the high charging rate.

I am sure in time that new software will be released and this might change the current charge rate, but currently we have no confirmed information surround this. The current charge is what BMWi feel is the correct and suitable charging rate.

I hope this helps and explains the situation"

Hmph!

 

[Bunter]

Email from bmw customer service..

"I have spoken to technical and the current charge rate is due to the new software that was applied to your car. This was applied to all i3’s and all current i3’s, as it helped to stabilise the charging process. This was implemented to stop the potential failure of additional parts due to the high charging rate.

I am sure in time that new software will be released and this might change the current charge rate, but currently we have no confirmed information surround this. The current charge is what BMWi feel is the correct and suitable charging rate.

I hope this helps and explains the situation"

Hmph!

Of course it most definitely is not applied to all i3s because they are not calling i3s in to have it done but are waiting for failures to trigger the software update.

Bill (i3 built in Feb 2014 and still charging at 7kW).

 

[kevinb61]

Email from bmw customer service..

"I have spoken to technical and the current charge rate is due to the new software that was applied to your car. This was applied to all i3’s and all current i3’s, as it helped to stabilise the charging process. This was implemented to stop the potential failure of additional parts due to the high charging rate.

I am sure in time that new software will be released and this might change the current charge rate, but currently we have no confirmed information surround this. The current charge is what BMWi feel is the correct and suitable charging rate.

I hope this helps and explains the situation"

Hmph!

Of course it most definitely is not applied to all i3s because they are not calling i3s in to have it done but are waiting for failures to trigger the software update.

Bill (i3 built in Feb 2014 and still charging at 7kW).

At least in the US I'm not sure that's true. there is a recall campaign to update the software.

 

[jadnashuanh]

At least in the US I'm not sure that's true. there is a recall campaign to update the software.

I've gotten both a phone call from corporate and e-mails requesting that I bring the vehicle in for the software update in the USA, so I agree. Part of it may be that some areas in the USA are MUCH warmer than almost anywhere in the UK, and the heat is likely a more critical issue. And, if it is cooler, even with the software changes, it may not need to reduce the charging rate. One has to consider that the prototype fleet ran for several years in many areas and that problem did not show up.

 

[LivingBetterThurEV]

I'm getting a 4.7kWh max charge rate on a new Rex we just picked up last Wednesday. All settings are max, no timers in use. At least the ChargePoint logs clearly show the consistent rate.

I assume that I should be receiving at least 7 or 7.2kWh rates. Will the dealer/BMW automatically notify everyone on the resolution/recall allowing the charge rates to be reset back to 100% ?
Called the dealer -waiting to hear...

I did not realize how stressful thus was going to be for the wife - as she watched the mileage available drop to --:-- below zero. (even though the Rex covered the distance during the early morning hours on our return home.

 

[noakey]

I'm getting a 4.7kWh max charge rate on a new Rex we just picked up last Wednesday. All settings are max, no timers in use. At least the ChargePoint logs clearly show the consistent rate.

I assume that I should be receiving at least 7 or 7.2kWh rates. Will the dealer/BMW automatically notify everyone on the resolution/recall allowing the charge rates to be reset back to 100% ?
Called the dealer -waiting to hear...

I did not realize how stressful thus was going to be for the wife - as she watched the mileage available drop to --:-- below zero. (even though the Rex covered the distance during the early morning hours on our return home.

Mine charged great at 7.2kw until it went bang and had the KLE replaced. Note I only get 5.2kw is frustrating. BMW told me that the software setting is thought the most appropriate for charging.. and no word of a hardware fix. Its 10 celcius (50F) at night in uk at the moment and I only get 5.2kw. I wonder how cold it has to be too get 7kw?

 

[jasleinstein]

We have had the i3 for three weeks. Over the last several days I noticed charging times growing much longer. My home automation system monitors power usage on several breakers, including the one used for EVs. The circuit is a 50 amp and I used the Clipper Creek HCS-40 charger cable. The car would never draw more than 2.8 kW. I took it to a level 2 charger and it still only drew 2.8 kW.
I took it in to BMW and the service manager quickly diagnosed the issue to be a bad KLE. Its no surprise when they called BMW parts supply they were told the KLEs may be on back order.
It's one thing to have the car charge more slowly. In talking to the service manager, he told me there are two charging paths for the i3.One is the KLE, the other is the MLE, the motor. Now I am concerned continuous current thru the motor might shorten the life of the motor.

I find it maddening BMW did not put the actual charge amount in the display. It is such a simple thing to do, I almost feel like BMW is trying to hide this issue as many customers probably don't realize their i3 are defective and just charge overnight.

Several owners have expressed "surprise" over the email sent out by BMW (portion copied here):
The BMW i3 Charging Electronics Control Unit (KLE) can be permanently damaged during hot ambient temperature charging. A temporary software solution will prevent damage to the KLE control unit and the charging rate will now be temperature dependant. In some cases the charging rate may be reduced by 30%. Full 7.4 kW charging will be restored with further improvements in late 2014.
The software update also includes measures that will solve the following issues:
• Air Conditioning issues for the Battery Electric i3
• Check Engine Light activation for the Range Extender i3
• 12V Battery discharge


In talking to the service manager: "charging rate will now be temperature dependant. In some cases the charging rate may be reduced by 30%." is not a true statement. With this change ALL charging will be cut back %30. Can someone verify this for me? Does anyone have the software update in and still have charging rates close to 7 kW? Charging times are critical as we have two electric cars and have only a 5 hour charging window for the i3.
thanks

 

[noakey]

We have had the i3 for three weeks. Over the last several days I noticed charging times growing much longer. My home automation system monitors power usage on several breakers, including the one used for EVs. The circuit is a 50 amp and I used the Clipper Creek HCS-40 charger cable. The car would never draw more than 2.8 kW. I took it to a level 2 charger and it still only drew 2.8 kW.
I took it in to BMW and the service manager quickly diagnosed the issue to be a bad KLE. Its no surprise when they called BMW parts supply they were told the KLEs may be on back order.
It's one thing to have the car charge more slowly. In talking to the service manager, he told me there are two charging paths for the i3.One is the KLE, the other is the MLE, the motor. Now I am concerned continuous current thru the motor might shorten the life of the motor.

I find it maddening BMW did not put the actual charge amount in the display. It is such a simple thing to do, I almost feel like BMW is trying to hide this issue as many customers probably don't realize their i3 are defective and just charge overnight.

Several owners have expressed "surprise" over the email sent out by BMW (portion copied here):
The BMW i3 Charging Electronics Control Unit (KLE) can be permanently damaged during hot ambient temperature charging. A temporary software solution will prevent damage to the KLE control unit and the charging rate will now be temperature dependant. In some cases the charging rate may be reduced by 30%. Full 7.4 kW charging will be restored with further improvements in late 2014.
The software update also includes measures that will solve the following issues:
• Air Conditioning issues for the Battery Electric i3
• Check Engine Light activation for the Range Extender i3
• 12V Battery discharge


In talking to the service manager: "charging rate will now be temperature dependant. In some cases the charging rate may be reduced by 30%." is not a true statement. With this change ALL charging will be cut back %30. Can someone verify this for me? Does anyone have the software update in and still have charging rates close to 7 kW? Charging times are critical as we have two electric cars and have only a 5 hour charging window for the i3.
thanks

Hi. Since the update my charging peaks at 5.4kw and quickly drops to 5.2kw.. then the usual gradual reduction for the final 10% or so.

I want told by the workshop and only discovered it at a little chef when I wanted to top up with an hour charge so I could make my round trip withouto another stop. My hour (£1.70) didn't give me the mileage I expected and that night at home I monitored it on my home energy meter.

i contacted customer service and they confirmed. Hmph. I look forward to the update be it hardware or software.

 

[M2140]

We have had the i3 for three weeks. Over the last several days I noticed charging times growing much longer. My home automation system monitors power usage on several breakers, including the one used for EVs. The circuit is a 50 amp and I used the Clipper Creek HCS-40 charger cable. The car would never draw more than 2.8 kW. I took it to a level 2 charger and it still only drew 2.8 kW.
I took it in to BMW and the service manager quickly diagnosed the issue to be a bad KLE. Its no surprise when they called BMW parts supply they were told the KLEs may be on back order.
It's one thing to have the car charge more slowly. In talking to the service manager, he told me there are two charging paths for the i3.One is the KLE, the other is the MLE, the motor. Now I am concerned continuous current thru the motor might shorten the life of the motor.

I find it maddening BMW did not put the actual charge amount in the display. It is such a simple thing to do, I almost feel like BMW is trying to hide this issue as many customers probably don't realize their i3 are defective and just charge overnight.

Several owners have expressed "surprise" over the email sent out by BMW (portion copied here):
The BMW i3 Charging Electronics Control Unit (KLE) can be permanently damaged during hot ambient temperature charging. A temporary software solution will prevent damage to the KLE control unit and the charging rate will now be temperature dependant. In some cases the charging rate may be reduced by 30%. Full 7.4 kW charging will be restored with further improvements in late 2014.
The software update also includes measures that will solve the following issues:
• Air Conditioning issues for the Battery Electric i3
• Check Engine Light activation for the Range Extender i3
• 12V Battery discharge


In talking to the service manager: "charging rate will now be temperature dependant. In some cases the charging rate may be reduced by 30%." is not a true statement. With this change ALL charging will be cut back %30. Can someone verify this for me? Does anyone have the software update in and still have charging rates close to 7 kW? Charging times are critical as we have two electric cars and have only a 5 hour charging window for the i3.
thanks

My car is currently in the shop and one of the issues being looked at is slow charging. I was getting reduced charing errors on the car and getting up to 6 hr recharge times while set to fast. The dealer tried to tell me that is was due to the Rex engine heating up the KLE. they said the KLE is not cooled like the battery and when the Rex is enabled it can overheat the KLE. I had to call the guy out on his BS excuse because when I had problems the Rex was never used. It was only because of the slow charging that i could not get a full charge in a reasonable time and I had to use the Rex to get home. Then, and only then did they admit there is a problem with the KLE. The dealer is trying to get a replacement KLE for my car, but BMW NA has not approved it because the slower charging right now is normal and intentional because the current KLE's have overheating issues. The dealer stated that the new part that fixes slow charging will not be available late in the year closer to december.

I loe the I3 but I'm very disappointed in the way BMW is handling service for these cars.

 

[donallen]

Some pedantry:

kWh (kilowatt hour) and kW (kilowatt) are regularly confused on this forum. This is akin to confusing miles with miles per hour. If someone asks what the i3's top speed is, you wouldn't answer "93 miles".

The rate at which a charger provides power is measured in kilowatts. Since watts are amps times volts, an EVSE (charger) providing 30 amps at 240 volts is providing 30 x 240 = 7200 watts or 7.2 kilowatts. The total amount of energy provided during a charging session is measured in kilowatt hours. Charging at 7.2 kilowatts for 2 hours provides 7.2 x 2 = 14.4 kilowatt hours of energy (assuming perfect efficiency).

I work in a related field, and have found it interesting when dissimilar items can be directly and accurately converted. Example, a watt is ultimately a unit of heat, it is 3.41 btu's of heat. So an i3 battery is carrying 22kw/75,000 btu's of energy. About 18kw/61,000 btu's is usable. Gasoline contains 115,000 btu's per gallon so the i3 battery holds 1/2 gallon of gas, basically.

You may work in a related field, but your post is confusingly sloppy and inaccurate. A watt is NOT a unit of heat, which is energy. A watt is a unit of POWER, which is energy/unit-time, the time-derivative of energy. An i3 battery does not carry "22 kw or 75,000 btus". You are conflating power (w) with energy (btus), apples and oranges. An i3 battery carries 22 kw-HOURS, which *is* a unit of heat=energy=work.