content: Nickel cadmium batteries had been used for decades. They are not suppressed technology. They have a low power density, they can only be charged a few hundred times, they will not last longer than 5 years and they will leak and grow "tin whiskers" which effectively kill the batteries. I used NiCd batteries extensively throughout the 80s and they just don't perform well. Laptops used them into the 90s and you got less than an hour of runtime per charge. They also have a "memory" which reduces their capacity if you don't discharge them enough before recharging. I don't know where you got your information on these batteries, but it's completely wrong. Also NiFe batteries are quite toxic and are not good for consumer applications due to that and their low power densities. Again you have bad information.