Quite probably not Pete. The cutoff circuit in a charger is matched to a thermistor which is in the battery. This senses the temperature and lets through the cut off voltage back to the charger at cutoff point. That's what the third pin is for in the charger plug.
Different systems have different thermistor types, so the eZee thermistor may not match the Heinzmann charger's cutoff circuit operating voltage.
I agree that NiMh is a better all purpose battery for e-bikes, and cut out is never suffered, but they have their inconveniences, like having to fully discharge to cut out every so often, and preferably using as much of the charge each time as possible before charging. Since performance of any battery drops as it discharges, for many people who do lots of short journeys that means quite a lot of their riding is at less than peak performance, just to get the charge used up.
With Li-ion, if cutoff problems can be avoided, life is much easier and more convenient. They should just be charged at any and every opportunity, this in turn meaning that performance is kept close to the optimum nearly all the time. That's it, just use, charge, and get the best performance, it couldn't be simpler. As a bonus, they average slightly higher voltage than NiMh, so the bike is marginally faster as well. The one problem is that they don't like continuous high current loadings, these only being possible within the imagination of e-bike suppliers and battery manufacturers.
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