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Internal battery questions?

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Has anyone ever opened up a battery pack to work on it? From what I've read, the cells are in sheets, correct? If so, how many sheets, and how many cells in a sheet? What does a "brick" of cells refer to then? Any pics out there? Anyone work on a pack themselves? Having a lot of experience in smaller versions of ni-cad and ni-mh packs in series, I'm quite curious....Nobody else makes replacement sheets for the roadster, right? Are the individual cells available?
 
Has anyone ever opened up a battery pack to work on it? From what I've read, the cells are in sheets, correct? If so, how many sheets, and how many cells in a sheet? What does a "brick" of cells refer to then? Any pics out there? Anyone work on a pack themselves? Having a lot of experience in smaller versions of ni-cad and ni-mh packs in series, I'm quite curious....Nobody else makes replacement sheets for the roadster, right? Are the individual cells available?
Roadster Technology - Battery

Sixty-nine cells are wired in parallel to create bricks. Ninety-nine bricks are connected in series to create sheets, and 11 sheets are inserted into the pack casing. In total, this creates a pack made up of 6,831 cells.
 
It also weighs 1000 lbs and has to be removed from the underside while on a lift. No easy task.

I agree, not that I would ever venture to remove a 1,000lb battery to begin with....each sheet will be close to 100lbs alone continuing to make the battery hard to service unless you really had all the correct equipment. Damaging the casing or sheets would be my largest concern. In pictures I've seen and at the local dealership, they have special holders and lifts to remove, install and work on the battery packs. I had the batteries leak tested in a 2009 Roadster last month. It was still under warranty (free).
 
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http://emeraldsequoia.com/55guts/index.html
 
From what I've heard, removing/installing the battery is a very time-consuming and quite difficult job even with the proper equipment.

Installing and removing the battery is not nearly as difficult as trying to open up the casing of the battery, replacing the cells and then trying to make it all work.

I think most any competent shop could probably remove and install the battery, it would be far more difficult to open up the casing replace sheets/bricks/cells, put it all back together and still have a working vehicle.
 
A few questions for Roadster owners (I hope this thread is appropriate enough):

The battery loses charge over time when not plugged in, *relatively* quickly so when coming from a full charge.
Does the Roadster actually draw power to make up for this loss when plugged in, or is keeping it connected enough to prevent power loss by applying voltage?
Is the discharge coming only from the monitoring/cooling systems or is it electrons "sneaking their way around the battery"?
How much power does the Roadster draw when connected but fully charged in a day/a week?
 
As for replacing the battery one of the larger challenges is you pull it from the bottom of the car and at 975lbs it is quite heavy and normal lifts for engines will not work.

As for the battery discharging you lose one ideal mile a day so it would take 180 days or a half year to discharge. If you keep it plugged in then yes it will wake up about once a day and top off using about .25KWH per day.
 
The Roadster will check once every 24 h if it has to add some charge to reach again its "Standard"- level, corresponding to a charge to about 85%. I have set the roadster to charge at 3 a.m. The loss between the end of a recharge then and 3 p.m. is not quantifiable with any accuracy. The sources of losses are diverse. I would expect that the largest losses are due to self discharge. I have not checked whether there is a steady load also between the charging cycles mentioned. The manual says: "When plugged in, the vehicle optimises the lifetime of the Battery by managing its charge level and temperature. The vehicle wakes up every 24 hours and, if needed, automatically initiates the charging process to keep the Battery at an optimum charge level."
 
From what I have seen, if you put the car in storage mode, the battery depletes about 0.5% a day. I believe most of that is due to the control processors, which are constantly running to monitor battery state and safety.

The exception is extremely hot conditions, when the battery requires active cooling to preserve its lifetime. In that case the drain can be much larger.

In Normal mode the car tops up once a day. In Storage mode it wakes up once a day to see if anything needs to be done, then immediately shuts down - unless the battery is very low in which case it tops up a bit.
 
Thank you for the responses.
I remember seeing a thread in the Model S section about the "Model S battery impossible to 'brick'", but I seem to be unable to find it right now. It did mention a non-linear discharge of the Roadster battery when stationary, which implied it being the Battery discharging itself and not the monitoring systems sucking up the power.
Money wise, the static discharge of 0.25 Wh/d to 0.4 Wh/d are a non issue.