Rear battery pack installed.

A new rear seat pan will be created to seal all the "orange" below the car.  The new battery box actually only intrudes into the cabin in the corners nearest the rear and only 5mm.  The other 99.5% of the battery housing sits below the existing body pan.  The rear seat cushion bottoms will be trimmed slightly, the rear passenger area will be have no perceivable change once the seats are in.

D a r n, forgot to get picture with the rear axle back in, it sits below the rightmost line of nuts and clears the box at all positions.  The top left of the pic is the rear tire well to help orient you.  The bolts will be trimmed to length before we are done.  The pack is held in by 7 8mm threaded rods, 5 are the original fuel tank mounting points, and two additional were added to prevent the battery pack from buckling above the axle.  Sleeves were placed on the threaded rods such that the joint could be pulled tight and cannot move up or down.

Look at that, the power lines come out right between the parking brake lines. :)  The original parking brakes are reattached with no routing changes, and the original brake lines are reattached with a 30mm change in routing.

NEXT STOP, Creating the front main power junction and control box. It will be made out of clear acrylic and house:
The two main power relays
The Pre-charge circuit
The Nissan Leaf BMS
The battery heaters relay
The charger junctions.

Rear Battery pack continued progress

The rear pack has been stuffed.

Kilovac LEV200H4ANA Solenoid The main POS must be turned on before the main cable leaving the pack is live.
The terminals were also covered with insulation.

Installing the bus bars and BMS wiring.

Installing the bus bars and BMS wiring.

Installing the bus bars and BMS wiring.

BMS wire management.

Wires left to right: Main solenoid control and confirmation, Main POS out, Main connection from 20 modules to 6 modules, heater connector, 12 pin BMS connector, heater connector.

20 module ready for install.

6 module connected and shield in place.

20 module beginning decent.

20 module 2 module deep.

20 module 95% deep.  Now the supports are unscrewed to finish lowering into place.

Next task, drill the stud holes through the lid and caulk the grooves to seal the box.
There will also be a breather hole in the lid center with desiccant.
Next step, put it up in the car.

Rear Battery Pack

We left you last year fitting the rear battery pack and finally figuring out the pins for the BMS.

Since then we had a dead 2001 GTI  with 200,000+ miles donated to the cause for parts as it is the same body.  The GTI is currently running errands around town until parts are needed.  We also paused for the push of several students completing formal education.

 Getting restarted.  A nearby lift was donated for a couple of hours, checked the fit again and finalized the installation points.


Hurrah for folks that work on car restoration more often, they had a better idea on holding the pack in place.


Perfect fit, front of rear battery box to frame rise for original fuel tank.  Original fuel tank mounting bolt holes to be reused.


Battery box pigtail s will exit directly into old exhaust tunnel.  Bottom of tunnel will be closed for protection.  Large hole is for the sensing wires.  Small holes are for the pos and neg leads.


Added brackets to hold rear of box to floor pan just fore and aft of rear frame beam.  Some days my welds are prettier than others.  Thank again to friends for the lessons and equipment usage.


The above picture of the welded brackets straddle the frame here.


Battery box complete.  Steel tubes will be placed between the brackets and the frame to allow for proper bolt tightening without air-gap.


Reconfiguration of safety plastic


Rear 6 pack installed in box with safety plastic


Rear main pack 20 modules with safety plastic and lifting brackets


Reminder of what it is supposed to look like.

Next stop, wiring all the sensor wires in the long pig-tails that go up to the BMS in the engine bay.

No Really we have not given up.

We have proceeded with the plan to place long pigtails from the rear battery box to the front BMS and power connection locations. It appears that Nissan used partially proprietary connectors for their BMS, BUT we figured out TODAY that they used standard headers on their circuit board. So rather than try to find the proper pin to refill the connector from Nissan (9 months lost), we figured out that we can use a standard connector and standard pins as the headers are standard. For us that means using connectors: TE Connectivity 1318747-1 025 ECU PLUG HSG ASSY 32P 1379668-1 24W PLUG HSG ASSY BLACK 1123343-1 CONTACT SOCKET The parts arrived today and fit. Moving forward...

No, We did not give up.

Car work did not stop entirely, I believe we left you at taking scans of the undercarriage so we could make the rear battery box.

David Scanner System

 We did finish scanning, and found the results to be within  6mm of accurate.  Close enough that we were confident our battery box dimensions would fit in the car.  We think the system would have worked MUCH better if we had been able to put the car on a lift and get the camera several feet away from the undercarriage instead of 8 inches.  In the end it took almost two weeks to stitch all the images together but if the distance to the camera had been several feet the system would have likely stitched itself.

Fuel Tank Bay

Note all the stars we added to the bay to help the computer and use manually align the images.

Battery Box installed

We made the battery box and got it up into the bay.  SEE it fits with zero clearance, but no "adjustment" was needed either.

Battery Box installed

The 4x4's will be replaced by the original battery box rails off of the Nissan Leaf battery pack. Since our pack is distributed front and rear the load here will be significantly less, so structural failure is less of a concern.

Battery Box from above

OK, the box did not quite fit.  The two corners stick up through the floor about 20mm.  A modified rear seat pan will be put in and the rear seat will be fully functional when we are done.

We have spent quite a bit of time looking at how we want to pass the wires in and out of the battery box.  Originally we were going to install multiple bulkhead pin connections, after much discussion, and a visit to see a friends Mini project, we have decided to use flexible conduit and really long pigtails running all the way up to the front of the car.  This reduces the number of pin crimps and connections by over 200 and hopefully increases reliability of the rear pack substantially.

Vacuum sensor

We got a vacuum sensor today.  The MAP sensor from a 1.8T VW can output analog for both pressure and vacuum.  This one came off the top of an intercooler.  Voltage output seems to go from 0.33 to 4.5V.  0.33-1.94V is vacuum.  We will read this into the DMOC controller and hopefully it can output a CAN code to the dashboard for an idiot light.

Charger cables

We have the Brusa NLG513 charger, but the charging cable that came with it has the wrong connector on it.

I have the J1772 to the charger.

I need the upper connector with the male pins.

This is the cable that came with the charger, but it obviously has the wrong end on it.  Anyone have the right cable for sale or willing to swap?

Rear battery box out for review

We have stumbled on the design of the rear battery box for almost a year now.  The configuration has not changed much in that time, just overall size nudges.

The plan is to slide the 6 modules into place and place threaded rods through the pack to hold them in place clamped.  The bus bars can then be installed on them with two wire leads protruding for connection to the 20 pack or the main output relay.  The two 10 packs are on the original Leaf plates and will have the bus bars applied to them again with a couple of leads extending.  The two packs will then be lowered into the box, secured with threaded rods, and the wiring connections completed.  A 5/8" plexiglass plate will be secured and sealed to the opening above the 20 pack.  The entire pack will be flipped upside down with the threaded rods now protruding from the top it will be lifted/the car may be lowered onto it with the rods passing through the floor pan for securing to the pack to the frame.  An independent skid plate will then be installed under the pack for debris protection.

We could use a little help figuring out the best wiring pattern. We have tried to upload both an excel worksheet we have been using to visualize the wiring in both xlsx and csv format.  They are plain sheets there should be no macros in them.  Anyone know how to upload them here?

This is the rear battery pack for the golf.  There are 26 modules in the pack, 4 stacks of 5, and 3 stacks of 2 as shown in the 3D images.  Note that the shorter stack is inline with the lowest rows in the 5 stacks.  Physical arrangement is FINAL, no moving modules...Each of the 3 boxes represents a connection on each battery module.  The middle connection is for sensing and may not be used for a power connection.  The outer connections represent + and -.  The entire set of 26 must be connected in series, + - + - +-......  Due to space constraints the outer gray set of connections should not be end points for the entire pack or transition to the 6 pack, but should route up or down in the rows of the 20 pack using flat bus bars as shown in the front box pictures.

Suggestions please.

The winning suggestion

This pattern looks like the best option.  It will allow the sections deeper in the box to be pre-connected leaving only one connection to make near the top of the box between the 6 pack and the left 10 pack.  This arrangement requires 13 long bus bar connections.  The original leaf pack only had 10.  So we are short 3.  It is simple enough to make the bus bars, but we would also like to reuse the Leaf orange safety housings like we did on the front boxes.  Anyone in the U.S. have some spare leaf protective covers we may use?

UPDATED:

Requires fewer long bus bars, and therefore we have enough parts.

Rear battery box scans and progress up front.

It took 3 days to for the scanning computer to crunch numbers.  It did not come anywhere close.  We did figure out that the save all scans button hand scrolled off screen, and we were able to save the 88 scans.  After almost two weeks of stitching scans together by hand, this is what we have.

You can see that we were able to get three larger sections completed in the scanner tool software.  The software loaded everything to memory, our 32 GB of memory was right at the edge and the system could not handle all three sections at once.  All the group scans were "fused" and then exported to .obj files that ProE could import.  Alignment in ProE is very difficult.  I am not convinced this effort will yield any usable results as we note many misaligned edges that appear to be out of place by 6 -10 mm.

In the mean time we also worked on the front batteries.  First thing, install a hoist...  We were given a free sling track usually used to hoist patients from a chair into a bath.  Rated at more than 500# and with 5' of travel this took an extra day to install, but we did not need to lift the completed pack.

Reaching up to install the bolts that tie the pack down to the frame.

This pack slid back to the other and was also bolted in.  The original Leaf wiring and bus bars were used.  The large orange loom at the right goes to the Leaf BMS.  The short orange is for the heaters one at the front of the packs and one at the rear.  The black loom is for the temp sensors.