I have an old NiteRider system that uses the 12v NiCad battery. The battery is only 3ys old and I believe that the charger is dead. Before I spend $40 for a new charger to determine if the battery is also toast, can I buy a cheaper charger and splice in the plug from the old unit?

If so, what do I need to pay attention to? The output on the old charger is 15.8v (or something similar, it is in the garage and I'm not ).