Ni-MH (Nickel metal hydride) batteries are more recent technology in rechargeable batteries, and are designed to be a substitute for 1.5V dry cell batteries. The batteries' performance is 30-50% better than Nickel cadmium rechargables. Note the high capacities listed below!
They should only be recharged in Ni-MH compatible chargers.
AA Cell 2500mAh Four Pack 
Manufacturer Code: NH15-2500 £5.49
AAA Cell 850mAh Two Pack 
Manufacturer Code: NH12-850 £2.49
C Cell 2500 mAh Two Pack 
Manufacturer Code: NH35-2500 £4.37
D Cell 2200mAh Two Pack 
Manufacturer Code: NH50-2200