Is there some kind of Moore's law governing capacity in batteries as there is in processor design? Perhaps a technology that's the equivalent of multi-core for batteries? It would seem there would have to be as devices get smaller malland ser and as as people become ever more reliant on them on a 24/7 cycle. I don't see that demand dissipating any time soon.
The problem before was in cotnrolling the batteries themal characteristics. Sometimes if the battery was being discharged too rapidly the temperature rose and created the issues already noted. Smae thing can happen when charging the batteries. I think the solution was in the modification of the chemistry involved.
In terms of energy storage the total energy stored is getting interesting. And any uncontrolled release of that energy has to be dealt with in a safe manner. consider a stick of dynamite. I am not sure exactly how much energy it stores but when it is released suddenly it has dramatic effects. If that same energy could be controlled and released gradually in the form of electric current it would make a fine storage device but probably not rechargeable.
If one had a Lithium-Ion type battery with the same energy storage potential as a comparable size stick of dynamite it would certainly warrant very careful attention to catastrophic failure modes.
As I recall from chemistry class, the most energetic chemical reaction is the conversion of H to H2. That is Monatomic Hydrogen binding with another free Hydrogen into diatomic Hydrogen, H2. I believe it also liberates an electron. Probably not possible to make a battery out of it.
What are the safety issues with the laminate-style lithium polymer batteries? It seemed that there was a lot of buzz a couple years ago about potential fires or even small explosions with lithium batteries, but I don't hear much about it anymore. Are these issues addressed in the polymer technology, laminate constructions or just in more robust housings? (Or not at all.)
You raised the big battery elephant in the room question at the end, Chuck, about capacity. Will capacities rise to 4.2A-hr or 4.4A-hr? This of course relates directly to product weight. If capacities don't rise, eventually (soon, actually) portable devices relying on these things will hit a design wall, and the heavier devices will end up being performance-impaired.
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