Picked up another cart

[BobBoyce]

I put the 2012 front seat back together, minus the front mount brackets and side handles, and bolted it to the rear seat mount. It's ugly and stained, like the seat backs, but I don't really care. Not worth taking a new picture of. It's just something to use around the homestead. It'll carry a passenger or two, or cargo if needed.

Bob

[BobBoyce]

Thanks to Andy, apgfl on the forum, I picked up a set of 7 used Nissan Leaf Lithium battery modules. While passing through Macon GA, I stopped at Fastenal and picked up a 8mm X 1 meter stainless steel threaded rod, a bag of 100 8mm stainless steel nuts, and a bag of 100 stainless steel lock washers. I cut the threaded rod into 4 sections of approx. 9-7/8" each. I used these to bolt the Leaf modules together into a battery pack. Photos attached. The plan is to incorporate these into the 2008 RXV 2+2 in place of the lead-acid battery pack. It will not initially have a BMS while I order the required electronics, but I do already have an onboard charger that I can use.

Bob

[Mooncarter]

Good job!

[BobBoyce]

I cut up one of the terminal mats from the 2018 Leaf pack and used pieces of that and bus bars from it to connect the cells on the lithium pack. Now I need to wire the BMS and mount it into a protective enclosure. I'm still waiting for the 48V relays, so cannot finish it until I get them.

[Buggieman18]

I'm salivating. I've got 4-12V that does great with a passenger, but put 4 adults and a kid on it and I'm running on fumes, that close to pushing it home. The radio kills it in a hurry. My wife said "get the lithiums" as we limped home, and didn't seem phased by the cost.

Got my brake relay, gonna hook it up to see if it clicks.

[yurtle]

Originally Posted by Buggieman18

I'm salivating. I've got 4-12V that does great with a passenger, but put 4 adults and a kid on it and I'm running on fumes, that close to pushing it home. The radio kills it in a hurry. My wife said "get the lithiums" as we limped home, and didn't seem phased by the cost.

Got my brake relay, gonna hook it up to see if it clicks.

She's a keeper.

[BobBoyce]

Originally Posted by Buggieman18

I'm salivating. I've got 4-12V that does great with a passenger, but put 4 adults and a kid on it and I'm running on fumes, that close to pushing it home. The radio kills it in a hurry. My wife said "get the lithiums" as we limped home, and didn't seem phased by the cost.

Got my brake relay, gonna hook it up to see if it clicks.

Definitely a keeper. You'll just have to oblige her.

I'm torn on my decision with the new 2018 Leaf modules. While I would love to put a set of them in my daily driver, it would not fit in the factory battery pack location over the rear axle. It would weigh in at about 250 pounds more than the 150 pound NiMH pack that is in there now. I think the factory BMS would be compatible, as it currently works with 7.6V nominal modules. The new 2018 Leaf module halves are 7.3V nominal, and will actually accept a higher charge voltage than the NiMH modules are ever charged to. I just don't really want to tie up 19 of the new Leaf modules for it. Especially considering that I have 2 spare low mileage NiMH packs stored for my daily driver.

I added the BMS wiring and BMS board to the lithium pack. No relays or any other wiring, just to let it start balancing the pack.

[agpfl]

Originally Posted by BobBoyce

I cut up one of the terminal mats from the 2018 Leaf pack and used pieces of that and bus bars from it to connect the cells on the lithium pack. Now I need to wire the BMS and mount it into a protective enclosure. I'm still waiting for the 48V relays, so cannot finish it until I get them.

Here is the enclosure I used

https://www.ebay.com/itm/Aluminum-en...8AAOSw54xUYcFE

Sent from my SM-G950U using Tapatalk

[BobBoyce]

Originally Posted by agpfl

Here is the enclosure I used

https://www.ebay.com/itm/Aluminum-en...8AAOSw54xUYcFE

Thank you Andy. I found one in Chicago IL, faster shipping than from China. It's tall enough to add both relays inside, and the power input/output sockets for the chargers AC power on the rear panel, as well as binding posts for the solenoid interlock loop. I want it to be an all in one interface solution. I want to thermal-bond the BMS PCBs Heatsink plate to the removable top plate that has the short fins on top. And cut a rectangular hole in the front panel for the BMS battery interface cable to directly plug into the PCB socket on the front end.

https://www.ebay.com/itm/142615126986

And here is the BMS PCB that I used

https://www.ebay.com/itm/302623423033

[BobBoyce]

Well, I ordered the case, a DPDT 48V relay, and a 100 mm X 100 mm square of double-sided thermal pad to bond the BMS PCB to the inside top of the case. The case and relay should arrive today. The double-sided thermal pad has yet to be tracking updated as dropped off at the post office, despite buying it 3 days ago. Using a DPDT relay allows only 1 relay to be used. The relay is marked as Solenoid on the drawing. Here is the US relay source...

https://www.ebay.com/itm/322535033946

And here is the thermal pad...

https://www.ebay.com/itm/202319390210

And I added a few pictures, and an updated BMS wiring diagram for the BMS showing one wiring configuration. Personally, I'll be switching the 120 VAC input for my charger instead of switching the DC output. It allows me to use a higher current charger, since the relay contacts are only 10A rated. My charger is rated for 15A of output at up to 59.3 VDC. The BMS will shut the charger off when the pack reaches the cutoff setting of 58.8 VDC.

The interlock circuit will be used to shut off power to the keyswitch when the undervolt cutoff setting is reached. I added a Reset/Override switch to allow overriding the BMS control or enabling the charger once it's in shutdown mode. This simple inexpensive BMS shares both functions on a single control output, so this is required to re-enable the charger once undervolt cutoff has activated. You simply activate the override to enable the charger for long enough to bring the voltage up so it will hold itself enabled.

Bob