I sure would not think so...just pull the old cells and insert the new ones...
That charging data is probably stored in non-volatile ROM/RAM chip somewhere, or maybe even the registry. I imagine that when you pull the old cells and put in the new ones the data will remain unchanged. The whole info thing is probably some relative way to indicate battery usage or projected life expectancy.
However, if the cells are already charged when you insert them, then your numbers might be off as the Fex21 normally considers these values are obtained whle charging the battery while within the unit itself.