Picked up another cart

[BobBoyce]

Sorry, wanted to post this earlier. But I dozed off...

I built the mounting brackets and bolted them to the ends of the pack.

The rear mount is a 6" W X 6" H X 1/4" aluminum plate, drilled and bolted to the rear of the pack. It has a 12" long 1-1/2" X 1/8" angle aluminum bolted to the bottom of it. This spaces the rear of the pack 1-1/2" above the surface it is mounted to. I took a photo of this view

The front mount is a 6" W X 3-1/4" H X 1/4" aluminum plate, drilled and bolted to the front of the pack. It has a 12" long 1-1/2" X 1/8" angle aluminum bolted to the bottomof it. This spaces the front of the pack 1-1/2" above the surface it is mounted to. I found the best SB120 connector mounting location, then drilled a pair of mounting holes. I mounted the SB120 connector with a pair of #10 X 32 X 1" stainless steel machine screws and nuts. I reused one of the stamped steel cover plates, cutting it to fit the mounting location. This is to protect the front of the battery pack terminal strip, retain the + wire, and provide a mounting surface for the BMS box. I took a photo of this view.

I turned the pack to the left and right and took photos.

I measured the + and - main battery power cables, crimped the Anderson 2 guage terminals to one end of each and 2 guage terminal lugs to the other ends. I soldered and heat shrinked both ends, then installed the cables and mounted the modified cover plate. I heat shrink wrapped the BMS pigtail with scrap pieces of leftover heat shrink tubing and stick the BMS connector into a slot between modules on top to keep it up and out of the way. I took a photo of the front to show this wiring.

I am still waiting for a few more parts to arrive before I can finish assembly of the BMS box and ready this pack for installation.

Bob

[USNBIP]

Looks good Bob. One question on yours, the stamped steel cover plate you reused that has the + wire coming out from behind it. Is that tied in to the battery packs? Where will that terminate to? Thanks.

[BobBoyce]

Originally Posted by USNBIP

Looks good Bob. One question on yours, the stamped steel cover plate you reused that has the + wire coming out from behind it. Is that tied in to the battery packs? Where will that terminate to? Thanks.

It's just a metal plate that covers and protects the terminal strip plastics. Normally those terminal strip plastics are not used when building Leaf packs for golf carts. I used them because I had them to get rid of. The metal plate has no electrical connections to the modules. It was part of the hardware that I removed from the 2018 Nissan Leaf battety pack that I bought a few weeks ago. There were a pair of those plates, one on the front of each end of a string of 12 dual modules that were bolted together with 4 long threaded rods. I routed the 2 guage positive cable under the top edge of that plate just to hold it in place. I had to cut a 3rd of the plate away to get it to fit the shorter pack and not interfere with the electrical connections at the ends. I plan to mount the BMS box on that plate with high strength double sided tape, rather than to stick it to the top of the pack like I had originally intended.

[BobBoyce]

Originally Posted by USNBIP

Looks good Bob. One question on yours, the stamped steel cover plate you reused that has the + wire coming out from behind it. Is that tied in to the battery packs? Where will that terminate to? Thanks.

I just realized that you were talking about the red "wire" coming out from behind the top right corner of the metal plate. It's a bundle of 15 wires that connect to each end of each cell of the 14 cells in series, as shown in the wiring diagram I provided for the BMS. These wires are visible in earlier photos, before I covered everything up. I had them draped over the top of the pack. That 15 pin connector plugs into the 15 pin socket at the end of the BMS board. Here are the photos.

[BobBoyce]

The binding posts that I had ordered arrived today. One package of 3 red/black pairs arrived with 2 out of 3 pairs having broken mounts on the black binding post. They must be too fragile to survive the post offices mail processing machines. I contacted the seller for replacement and sent him a photo...

I'll have to wait for replacements to arrive intact before I can finish.

I used the one pair that survived along with a set of small red binding posts to build a charger control box that will accept the charger control signal from the BMS. I used a weather resistant outlet in the box for the onboard charger, and a 10' power cord. Included photos of this box...

Bob

[BobBoyce]

Not wanting to wait on the binding posts to arrive, I went to Home Depot and picked up some rubber washers and some nylon washers, and rebuilt the binding post mounts to use those. I finished assembly of the BMS box. Here are the photos...

[BobBoyce]

I decided to go ahead and mount the BMS box (with heavy duty double-sided tape) to the top of the pack. It is more weather resistant in that location and position. I cut off the pieced together heat shrink tubing on the 15 BMS cell sense wires and used a single 6" piece of black 1/2" sealer lined heat shrink tubing. A photo of the BMS box and an overall photo...

[cgtech]

[BobBoyce]

The lithium pack is now completed and ready for testing and installation.

The BMS is completey wired and was left running overnight to do a full balance. This lowered total pack voltage from 59.9 to 59.8 VDC. I left the charger control box unplugged so the relay would not draw any current. The charger control pigtail can be seen on the top rear center. It provides pack voltage when the BMS has the charger control turned on. Here are photos of the pack front, side, and rear...

Bob

[BobBoyce]

Time for testing the charger control box and bypass switch.

The first picture is the test to measure the charger control relay voltage coming from the BMS, measured at the relay control pigtail at the rear top center of the pack. When the BMS is commanding the charger to be on, this output will read full pack voltage.

The second picture is the Charger Control Box status with the relay control pigtail unplugged, and the Bypass switch turned off. The test meter shows open circuit on the Charger Control Box output.

The third picture is the Charger Control Box status with the relay control pigtail unplugged, and the Bypass switch turned on. The test meter shows closed circuit on the Charger Control Box output.

The fourth picture is the Charger Control Box status with the relay control pigtail plugged in, and the Bypass switch turned off. The test meter shows closed circuit on the Charger Control Box output.

All tests have passed. Now we wait for good weather so the lithium pack and charger control box can be installed into the 2008 RXV.

If you wonder why the electrical outlet is installed with the ground hole up, that is the way we tend to install them in industrial/commercial installations. The larger round ground lug supports the plug/cord weight better than the vertical blades do. It places a bit less stress on the hot and neutral contacts, resulting in a bit of extended service life for the outlet...