Pics/Info: Inside the battery pack

[jat]

So, finished my first 500mA discharge curve for a single cell from a Model S module. Charged to 4.2V @ 1A constant-current, then constant-voltage until current dropped to 120mA, 5 minute delay, then discharge at 500mA until voltage read 2.85V. Test was done using FMA Powerlab 8 and the custom settings above. After charging the cell settled to a resting voltage of about 4.16V.

Have you charged a whole module using your PowerLab 8? It seems like either you could hook up the cell voltages from the connector to the BMS board to the balance wires to the PL8, or you could rely on the BMS board doing the balancing itself.

 

[Jessing]

Dear All,

Does anyone here have some information of the valves in the bottom of the battery casing?

There are 6 of them shown on wk057' picture 2014-09-09 2021.21.31.jpg. wk057 call them "some kind of safety relief vales".

I believe they are meand to drain the battery casing from condensate, and at the same time to block any inflow of water from the inside, fx if the car is parked in 6-7 inches of water, after heavy rain. A one-way-valve in other words.

I need similar valves for a project, and I have searched everywhere I can imagin, but without luck.

I also asked wk057 if he had some of them in excess, but unfortunately he throw them out as they was not useful for his project. :-/

Any information, such as a brand, vendor, data, more pictures, or a link to an alternative valve with similar funktion would be helpful ... and ofcourse; if anyone has one or more samples, I would be very interested to buy.

Thanks :smile:

 

[Ingineer]

They are fire vents. They are designed to let excess pressure vent safely underneath the car while not allowing air (or water) into the pack in normal circumstances. There are 6 in each of the 15 "brick" compartments which are isolated from each other. If there is ever enough moisture in the pack to need draining, your pack is already done. Other than the 1-way vents, the pack is pretty well sealed.

 

[Otmar]

You can get more details of what they may be using by viewing these patents:

http://www.faqs.org/patents/app/20120231306

http://www.faqs.org/patents/app/20120237803

 

[zZZzzzSnooze]

They can have a P200DL & 200D Model S Today!! that battery alone would cost around $30K US.

Just looking at the pictures of the open 85kW battery pack, They can bump up the capacity to 200kW, boosting range from 435km on the P90DL to 970km & from 460km on the 90D to 1,030km... The P200DL & 200D can be made now... Charge times to 80% on the P200DL & the 200D would take something like 1H:29M to 80% & fully charged would take 2H:47M on a Supercharger. At home on a 240V outlet would take 26+ hours. 110 volt? lol 6 days...

I was just looking at the pictures, I could be wrong...! There is 7,040 batteries in a 85kW Model S battery with a fully charged voltage of 336DCV. 16x 21 volt fully charged banks with 440x 1850 batteries, and that 21V bank is divided into 5x 4.2 volt 1,000mAh capacity 1850 battery connected in parallel. Samsung has a 2.5Ah 1850 battery that can be discharged at 25A. Panasonic has even a larger capacity 3.4Ah but a discharge rate of 3A... but you have 88 of them connected in parallel, The Panasonic should still be enough to power the Model S to its full power. Wow 272kW Model S battery, and them Panasonic's are at least twice the cost of the Samsung!!

With Panasonic batteries charge times to 80% on the P272DL & the 272D would take something like 2H to 80% & fully charged would take 3H:47M on a Supercharger. At home on a 240V outlet would take 36+ hours. 110 volt? 9 days...

Opened 85kW Model S battery

Voltage on a Bank

Voltage on a 85kW Model S battery?

Front dual layer banks

Thanks for the Pics/Info wk057!

 

[Ingineer]

You are a bit off: In the 85/90 pack there are 16 modules in there each containing 444 cells for a total of 7,104. In each module there are 6 series strings of 74 cells in parallel, so that's essentially 96 large cells in series for the total pack.

Fully charged the pack is at around 400 volts, so that makes about 4.17 volts per cell.

 

[Andyw2100]

Thanks for the Pics/Info wk057!

Welcome to the forums!

Just a bit of advice: if you're going to use someone else's photos in the way you just did, you may want to note that the photos are someone else's BEFORE you start including them and describing them. As I was reading your post I was thinking to myself, "Is this guy really taking credit for Jason's pictures," until I got to the very end, where you did include the note above. A simple note along the lines of, "the following pictures were taken by wk057" in the future would avoid any such confusion.

 

[Mucteba]

Hey wk057, any idea how did tesla engineers spot welded individual fuse to each cell, those wire are so small, which material and method did they use? BTW you did some impressive work out there..

 

[tornado7]

Please excuse me for digging in the archives. I found this thread most interesting and do now understand my car much better thanks to your efforts, wk057.

In testing with a salvage vehicle and pack, the balancing circuits would never enable until the car was at the constant-voltage stage of the charge cycle, around 93+%.

So what you and apacheguy were saying 2 years ago is that despite the fact that the packs are so well balanced (delta V less than 0.01 on the 96 cells managed by the BMS) balancing does not (!) occur on any state of charge below 93%? This would mean that in many of the vehicles on the road there would never be a balancing event being triggered as the users oftentimes do not charge above 90% and also do not let there vehicles rest on that level for any significant amount of time (with balancing taking 10+ hours).

You are talking about during charging above. What about just resting in the garage, say at 65% state of charge?

 

[LargeHamCollider]

@Mucteba The individual fuses/wires are welded with ultrasonic welders.

 

[pers1]

Hey wk057
100D no longer 100kWh back to the 90D
When u did the teardown og the P100D u got these numbers:
100D US Measured VIN 159k
Advertised Full Pack 100 kWh
Nominal Full Pack 102.4 kWh
Energy Buffer 4 kWh
Usabel Full Pack 98.4 kWh

I used both TM Spy and Scan My Tesla app and got these numbers form 2 different Model X 100D here in Norway, they are not P models.

100D Measured VIN JF08XXXX (mine)
Advertised Full Pack 100 kWh
Advertised Full Pack 96.9 kWh
Energy Buffer 4 kWh
Usabel Full Pack 92.9 kWh
Only with 40.6Km / 25.22 Miles on the odometer Brand New at delivery. Finished in production january 14th 2018 and shipped to Norway

100D Measured Vin ?
Advertised Full Pack 100 kWh
Nominal Full Pack 97.5 kWh
Energy Buffer 4 kWh
Usabel Full Pack 93.5 kWh
Only with 3719Km / 2310,87 Miles on the odometer

Why are the numbers "so" different, have Tesla done something with the batteries or cutting kWh to increase proffit margines?
Back to 90D "gate"

 

[piwhy]

Hello,
I'm looking for the reference of the cooling connectors used on the P100D battery packs. These connectors : Google Image Result for https://cdn.teslarati.com/wp-content/uploads/2017/01/Tesla-p100d-battery-cooling-architecture.jpg
I'd like to use the cooling system on some modules but I can't find used connectors from a Tesla or the reference of these connectors.
Thank you.

 

[notnitinchopra]

Hey wk057, thanks for sharing the images of the teardown of the battery pack.

Right now I'm designing my battery pack and in this, I need to stack a module on top of a similar module. This is similar to the two modules stacked in Model S.

Can you tell me how are they mounted in such fashion so I can get some inspiration for my project?

Thanks!

 

[ACDriveMotor]

Great pics thanks for sharing!

 

[Ande]

Where does it dissipate the heat when loading one cell for balancing purposes ? - the BMS PCB does not contain any power components.

 

[lolachampcar]

I remember looking at the (TI I think) balancing chip and there were independent switches to separate resistors for bleeding off energy. Its not that much energy so the components are surface mount and reasonably small.

 

[arg]

You can see the actual resistors in this post earlier in the thread: Pics/Info: Inside the battery pack

(though note that the text below the photo gets the resistor value wrong - someone corrects it a few posts later).

 

[Ande]

Yes, I did spot those at an earlier occasion when this thread started, but 0.4W is ridiculously low compared to what I expected.. I were looking for at least 30-60W or so. no wonder those that obsess about charging to 100% have a loooong wait.

 

[World citizen]

Hi, I am new to this forum. I teresting original post and comments from the community. I have a question regarding BMS board. I am hoping you'll be able to answer. I bought 4 Type S Tesla batteries to use as 48V storage battery bank in a Solar Electricity production off-grid project. So the radiator fluid was drained out already. If I leave the BMS board on the module and charge the battery bank with solar panels, will it do any harm to the battery? In other words, will the software on BMS malfunction as it can't control the temperature by pumping coolant? Or will it still balance cells?
BTW I am planning on using MPP hybrid 6048 splitphase inverter (Taiwan company), these can be connected in parallel to get 3-phase electricity.
Appreciate your effort and time in sharing your findings with the world.

 

[cduzz]

Sorry to pile onto a Deep Necropost, but do you have any thoughts as to if a 4680 cell would fit into the tub of the tub of the main battery case (IE without being inside a module)?