how much time the 24v nimh can hold without carging?when the battery die?

how much time the 24v nimh can hold without carging?when the battery die?assuming the battery is in good working condition.This is because i have one without charging,my charger drop out from my hands and go to the floor .when i connect the charger to the outlet it sounds a little "wisper".Dont charge at all.I was leave the battery without charge for about two months.If i try to charge the battery on those days i expect good results?thanks for the attention.