@rplst8 posted:Internal protection is not unique to Li-ion.
I do not doubt that some do have that protection. I know the ones I use for my RC planes do not. I think we agree, no matter which chemistry you use, PCB should be built in, else you run the risk of draining them too low in a model train application.
I also know that my LiPo's need a special balance charger and should be charged in a safe bag or box. If the model train user wants a permanent battery setup, Lipo's do not lend themselves to be very convenient to do that.
This Short of a LiIon Battery Test Video convinced me LiIon with PCB would be the ONLY battery I would put in my trains. I like my trains and my house and would like to keep them.
Ron