I have a Phylion XH370-10J 36v 10ah battery that is 5 years old. It's range is now 9 miles and it cuts out under load sometimes. I bought another 36v 10ah battery last week to replace it with.
The way the current Phylion one is wired up in the case is confusing me.

There are two negative wires, a black one for discharge socket and orange for the charge socket. There is only one red live wire emerging from the battery which goes a fuse then splits off to the discharge socket and the charge socket. The bike allegedly has regenerative braking and it also has a charge socket on the bike which I never use.
The battery pack I want to replace it with has 4 wires emerging. Two of them are thick red and black wires for discharge, and the other two are thinner pink and orange wires for charging, the orange is negative.
I don't know how to connect it up. I'm not good at soldering and I need quite a few practice runs. I thought I could just disconnect the bullet connectors on the old battery and connect the new battery, but they are stuck and I don't want to force them yet. And I don't know what to do about the extra wire.
Should I connect the two thicker ones directly to the discharge socket, and the thinner ones to the charge socket? Would this cause problems if the battery tries to charge through the discharge port when regenerating downhill or if the charge socket on the bike is used instead of the battery? Or do I need to hook it up the way the old battery is in there now, with the live discharge also connected to the charge socket?
The way the current Phylion one is wired up in the case is confusing me.

There are two negative wires, a black one for discharge socket and orange for the charge socket. There is only one red live wire emerging from the battery which goes a fuse then splits off to the discharge socket and the charge socket. The bike allegedly has regenerative braking and it also has a charge socket on the bike which I never use.
The battery pack I want to replace it with has 4 wires emerging. Two of them are thick red and black wires for discharge, and the other two are thinner pink and orange wires for charging, the orange is negative.
I don't know how to connect it up. I'm not good at soldering and I need quite a few practice runs. I thought I could just disconnect the bullet connectors on the old battery and connect the new battery, but they are stuck and I don't want to force them yet. And I don't know what to do about the extra wire.
Should I connect the two thicker ones directly to the discharge socket, and the thinner ones to the charge socket? Would this cause problems if the battery tries to charge through the discharge port when regenerating downhill or if the charge socket on the bike is used instead of the battery? Or do I need to hook it up the way the old battery is in there now, with the live discharge also connected to the charge socket?