Help Needed - Lifepo4 Battery Plans for Ryobi RM480e Tractor

[gwang_hoops]

We installed our four new 50Ah LiFePo4 batteries to replace the 48v battery pack (after charging each to 100% with a 12v LiFePo4 specific charger) and our RM480e tractor works perfectly. We also ordered a 48v LiFePo4 charger and an EzGo connector. There are only two wires coming from the charger and there are three on the EzGo connector. Did you have to make any changes or modifications to the wiring on to the RM480e to get the LiFePo4 charger to work? Thanks!

nope. AFAIK, the third pin used to be for the AGM thermistor and might be necessary for mower lockout during charging but I didn't care enough to look into it.

 

[Ampster]

There are only two wires coming from the charger and there are three on the EzGo connector.

I suspect one of those is a ground. Is it like this?

 

[jberger]

The 3rd prong is the "inhibit" feature on the EZGO, it's designed to prevent you from driving off when the charger is connected.
I know it can be removed on EZGO, I don't know the process for Ryobi.

 

[JimmySteel]

Thanks to everyone who answered. We are going to wire up the charger today and add some spacers to the battery pack and then give it real try mowing. Our last step (hopefully) will be installing the new gauge.

 

[JimmySteel]

We received our new 50Ah LiFePo4 batteries, charged them up, installed them to replace the 48v battery pack and our RM480e tractor works exactly as it should. We also ordered a 48v LiFePo4 charger. There are only two wires coming from the charger. We wired them up using the original connector from the Ryobi charger and the battery pack is not drawing any power form the charger. Does anyone know if the third pin needs to be connected to something for the charger to work? Thanks!

 

[JimmySteel]

Okay, I screwed up. One of the pins was pushed back just enough and was not making good contact. For the moment we have the two bottom pins inserted manually and the charger is working fine now at 12 amps. Do you know what to connect the third pin to? That was the green wire from the charger. Does this stop someone from turning on the tractor with the charger attached?

 

[gwang_hoops]

Okay, I screwed up. One of the pins was pushed back just enough and was not making good contact. For the moment we have the two bottom pins inserted manually and the charger is working fine now at 12 amps. Do you know what to connect the third pin to? That was the green wire from the charger. Does this stop someone from turning on the tractor with the charger attached?

AFAIK, the Ryobi AGM battery charger used it for charging (if you left out or disconnected the thermistor connected to the old batteries, it wouldn't charge) and on the mower side it locked out mower operation while charging.