JRP3
Hyperactive Member
I'd be surprised of any type of balancing was taking place at lower SOC's, and most balancers that I'm aware of do most of their work near the end of charge.
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Model S Technical / Mechanical Issues
- Thread starter DrComputer
- Start date
JRP3
Hyperactive Member
My understanding, and it could be bad since it's based on what I've read rather than personal expertise, is that during a slow charge the SOC tends to level out between the cells because the cells with the highest SOC tend to take a bit less over a given time period. That doesn't happen during a rapid charge. Of course, there are the questions of "what constitutes slowly" and "is there enough variance in the individual cell's rate of charge in this situation to make a significant difference".
The biggest problem I see with all the kind suggestions by Forum members to Range charge repeatedly and then discharge the battery to minimum is that it is completely contrary to what it says in Tesla's manuals. If a Service Center tells me in writing on a Repair Order to follow that procedure, I would gladly do it. I have been following Tesla's instructions to charge the battery daily between 60%-70% and keep Range Charging to a minimum.
steve841
Active Member
I tend to lean to your thinking .... (less keeping plugged in at all times per manual). I charge to 70% and try not to let range drop below 60 miles of rated range.
Happily have no clue what a range charge will get me.
JRP3
Hyperactive Member
What you are describing could only happen when a cell is full or nearly so. Say you have two cells, one is at 3.44V and the other is at 3.50V. Assuming similar effective internal resistance* both cells will keep accepting charge at the same rate. Now at higher voltage/SOC if one of them is nearly full then it may start to shed excess charge as heat due to an increase in effective internal resistance. However you don't really want that to happen, you want an external balancer to start dumping some charge either through a resistor or by shuttling it to a lower cell. Complicating this is the effective internal resistance of one cell could be higher than another and that cell may show a higher voltage when charging even though it's not actually at a higher SOC. Lower charge currents help avoid that, and ideally measurements would be taken after the charging has stopped at resting voltages, which eliminates the internal resistance issue.
*I'm using the term "effective internal resistance" because it's not really resistance but diffusion rates of ions through the SEI layer and into the structure of the electrode.
Bugeater
Member
But what constitutes a slow rate of charging? Does my HPWC at 80 amps? Or does it take 20 amps or less?
JRP3
Hyperactive Member
No matter what charger you use the end of charge rate still tapers down. Leaving it plugged in after charging should allow extended balancing to occur.
InTheShadows
Active Member
In regards to the klunking sound from the motor I described earlier.
The service center checked all suspension points and retorqued them. They also checked the motor mounts and they are fine too. The determined that the sound is coming from within the motor.
They let me take our car home and they will be bringing us a s60 loaner next week so they can do a drivetrain diagnostics with the engineering team from CA. I was told that they may end up replacing the drive train.
They would have kept it today but they only have s60 loaners and I need an 85 to get home. (I was puzzled by the s60 loaners, I thought they were only doing p85+ loaners, perhaps they are trade ins from people buying the p85+'s?) I will let you know what the issue is once they find it.
Updated: oh yea, they told me they didn't notice it with creep turned on. Since we have always driven stick, we keep creep turned off. I think the creep function hides it by always having torque on the motor.
The service center checked all suspension points and retorqued them. They also checked the motor mounts and they are fine too. The determined that the sound is coming from within the motor.
They let me take our car home and they will be bringing us a s60 loaner next week so they can do a drivetrain diagnostics with the engineering team from CA. I was told that they may end up replacing the drive train.
They would have kept it today but they only have s60 loaners and I need an 85 to get home. (I was puzzled by the s60 loaners, I thought they were only doing p85+ loaners, perhaps they are trade ins from people buying the p85+'s?) I will let you know what the issue is once they find it.
Updated: oh yea, they told me they didn't notice it with creep turned on. Since we have always driven stick, we keep creep turned off. I think the creep function hides it by always having torque on the motor.
Forty Creek
Member
Thanks for the update on this. I am still waiting for a call back from Tesla and continue to have the klunk/knock sound. Opposite to your experience, I seemed to start hearing it sometime after turning creep on. It doesn't just happen from a dead stop-to-go movement. Also happens with acceleration from moderately low speeds or speed reduction from a lower pace.
gg_got_a_tesla
Model S: VIN 65513, Model 3: VIN 1913
Aargh. This front passenger door handle is giving me a headache. Have to take it into the service center for the third time in 6 weeks. First, the handle used to come out but not let the door be opened. Tesla replaced the old-style handle with a new one. Then, the window started making a clunking sound as it went up or down; turned out that the door handle harness was loose. Now, there's a constant, loud rattle from the vicinity of the handle that I have to drown out with music.
teslasguy
MSP P#1117
UMC blinks red and stopped working. I unplugged my car today and noticed after getting into the car that I only had 138 rated miles even though I had the charge limit set to about 180 miles. When I got home I plugged the UMC in and charge port went immediately solid red and saw a message on the dash that said bad charge cable. I removed and tried again. No good. Unplugged the 14-50 plug an replugged. No good reset the UMC no good. The UMC always blinks red 3 times, pauses and blinks 3 red again. Called SC and they said it sounded like a bad cable and asked if I could bring the car in tomorrow to check the cable. I said a neighbor has an S and I could ask him if I can try his UMC. They said great so I went over to his house and plugged his cable in. Immediately red. So the SC said that it looks like a problem with my car. Well...just got a call from my neighbor. He just got home with his S and his charge port goes immediately red when he plugs in. His son told him about me stopping by to test his cable with my car. So he then reset his UMC and tried again. No good. His charge port now goes solid red when plugging in. Looks like whatever is wrong with my car has now fubarred his UMC. Hopefully his now messed up UMC didn't also damage his car. Anyone else have anything like this happen?
This can happen if there is not a good connection with the ground and pilot pins, I'd inspect the connectors to see if there is any grease, dirt, sludge, etc. in those smaller holes in the connector. While there is a remote possibility of a car damaging the UMC electronics, I'd start with the mechanical reasons first.
teslasguy
MSP P#1117
No grid issues I'm aware of. Our development is about 10 years old and all underground utilities. We never lost power all winter even when other areas did. I've been using my setup for about a year and a half since I got my car with no issues. I unplugged the adapter from the outlet and removed it from the UMC cable. Connectors all look good. No overheating signs or deformities. My neighbors UMC had also been working fine until I plugged it into my car and now it's no longer working with his car. Taking my car and cable to the SC this morning along with my neighbor's cable. I'll post an update when they figure out what's going on.
teslasguy
MSP P#1117
So the SC determined that my charge port is bad and that in turn fubarred both my and my neighbor's UMCs. They are replacing the charge port and giving us each new UMCs.
RobsJester
Member
Sadly Darth, a new window and labor cost $1,444
• $875 for the glass, labor is 490 +tax (almost twice the cost to replace the windshield of a "S Class" Merc - $800+/-)
I have an early VIN (03818) and this is the second window crack originating from the passenger "A" Pillar. The first was replaced in Dana Beach, FL without any question last summer. Although the crack looks eerily similar to the last break, I've been told it failed the ball-point pen check, so I'm out the insurance deductible - and my insurance company is out a grand on top of that.
There is always a silver-lining, for the last month, I've watched the crack slowly grow, marking the spiderweb's progress like a proud mother penciling her first-born's height in a doorframe, at least I now have something to do while sitting in LA traffic.
To those in the know, a ranger preformed Sb-13-10-006 on the passenger "A" pillar to reduce the "popping" noises when driving, but I doubt a flathead screwdriver and mallet solved the underlying body flex that could be contributing multiple cracking windshields.
Here's a link to the pict: Windshield2_zpsfd9b1f80.jpg Photo by roadhd | Photobucket
Don't get me wrong, I love the car, company, and brand; I'm just hope my car doesn't continue to pop $1,488 windshields every six months.
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