Hi Garry. Thoses cells may behave just as good as new. Some of my best cells are from 2008 and 2009. These cells I use in 3S lights regularly. Of course, I recommend you monitor the cells for a while before you start subjecting them to higher currents and using them in series. I just watch for losing voltage, getting hot while charging, and check the capacity now and then. I always use a hobby charger to make sure the cells I use in series have similar capacities.