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First Diy Golf Cart Battery

Dadkins

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Mar 27, 2022
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ordering everything to make my first lifepo4 pack. I'm going with 16 105ah cells and the JBD 48v 200a bms. I still need to get a charger so I'm looking for suggestions on that. Outside of a box to put everything in is there any other parts i will need to hook everything up safely? the batteries will already have bus bars.
 
Does the BMS have Bluetooth connection? If so, get the app to be able to manage your settings and turn the battery off.

You might consider a coulomb meter for a "fuel gauge". Large terminal strips can make it easier to connect and disconnect the battery or connect additional loads to the battery. That way you have just one set of battery connections to the terminal bar and you can leave them along, for the most part.
 
Does the BMS have Bluetooth connection? If so, get the app to be able to manage your settings and turn the battery off.

You might consider a coulomb meter for a "fuel gauge". Large terminal strips can make it easier to connect and disconnect the battery or connect additional loads to the battery. That way you have just one set of battery connections to the terminal bar and you can leave them along, for the most part.
Yes it does have Bluetooth! I’ll look into that meter. I will probably add the large terminal strips to hook everything to it. I will only be using it to power the cart and then all the accessories will be hooked to a separate 12v
 
Yes it does have Bluetooth! I’ll look into that meter. I will probably add the large terminal strips to hook everything to it. I will only be using it to power the cart and then all the accessories will be hooked to a separate 12v
Mine is similar. I have a 36v to 12v DC to DC converter for 12v LED lights, USB charger, and 12v socket. That converter is on a relay with the coil connected to the main key switch. I have a smaller 12v terminal strip under the dash so I just bring one 12v pair up to that strip and then power all of the 12v stuff from that point.

Meter same/similar to this one.

My comment on turning the battery off at the BMS, if you have the BMS connections well insulated, after turning off the BMS, my battery pack can be disconnected from my terminal bar and the leads not be energized, which is nice.

This offering has the cells under compression and connected already, for a quick build.
 
Mine is similar. I have a 36v to 12v DC to DC converter for 12v LED lights, USB charger, and 12v socket. That converter is on a relay with the coil connected to the main key switch. I have a smaller 12v terminal strip under the dash so I just bring one 12v pair up to that strip and then power all of the 12v stuff from that point.

Meter same/similar to this one.

My comment on turning the battery off at the BMS, if you have the BMS connections well insulated, after turning off the BMS, my battery pack can be disconnected from my terminal bar and the leads not be energized, which is nice.

This offering has the cells under compression and connected already, for a quick build.
Thanks for the info! did you add any other fuses or anything like that? what did you put your cells in?
 
I built 2, 10 cell Li-ion packs from some used 64ah cells (testing about 52ah). I taped them with some stranded tape and then shrink wrapped each pack. The DC to DC converter, the lights, and my power bar with the 12v socket and USB sockets, all have in-line fuses. So I didn't add additional fuses. I am depending on the BMS to protect each pack. Each pack has it's own BMS inside the pack. The packs are in parallel at the main terminal bar for the positive and at the battery side of the shunt (meter) for the negative. The other side of the shunt is to the main negative terminal bar.

See photo below. The rat's nest of small wires and wire nuts, I have since reworked and cleaned up. That is my 36v to 12v wiring.
 

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I built 2, 10 cell Li-ion packs from some used 64ah cells (testing about 52ah). I taped them with some stranded tape and then shrink wrapped each pack. The DC to DC converter, the lights, and my power bar with the 12v socket and USB sockets, all have in-line fuses. So I didn't add additional fuses. I am depending on the BMS to protect each pack. Each pack has it's own BMS inside the pack. The packs are in parallel at the main terminal bar for the positive and at the battery side of the shunt (meter) for the negative. The other side of the shunt is to the main negative terminal bar.

See photo below. The rat's nest of small wires and wire nuts, I have since reworked and cleaned up. That is my 36v to 12v wiring.
Awesome! what did you use for a charger? im wondering if i can buy an ezgo charger handle and attach it to whatever lithium charger i decide on. that what i can just use the stock charging receptacle.
 
People will argue about charging batteries and about battery chargers. While a standard lead acid charger might work okay for your LiFePo4 batteries, I like to be able to control my "charge to" voltage and keep it below normal max cell voltage. I am using a cheap power supply that is set to the voltage that I desire. It is current limited to 10 amps, so charges at 10 amps until the voltage is almost to my set point and then the current naturally approaches zero as the battery voltage comes up to the set point. It will charge fully in about 20 hours. I might get a larger power supply or maybe a second one of this type if I want to charge faster. I also have some solar chargers that I might end up using.
 
Did you complete your build yet? Consider using the BMS with an external relay that controls the keyswitch to the controller. This way you aren't limited by the max amps of the BMS.
 
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