I had a fair bit of experience with Lithium-Polymer cells with electric model aeroplanes.
First there was Nickel-Cadmium cells, which were heavy. Then came Nickel-Metal Hydride which were heavy too but gave a bit more power for a little longer.
Li-Pos were met with a lot of suspicion when they first appeared. They were much lighter and much more powerful than anything before, but required special chargers and speed controllers... And were very expensive.!
I saw plenty go up in flames. it was always due to mis-use of some sort, either the wrong charger or charging regime, Poor ventilation in the model, crash damage or a direct short.
I remember connecting one into a model wrong and instantly ripped it out, chucking it over my shoulder in one movement. It was smoking by the time it passed my ear and on fire when it landed.
They swell if they are on the way out and become a little more volatile at that stage. If the cells were a write off, the trick would be to drop a scalpel into them and watch the fizz and clouds of toxic smoke. Flames would sometimes issue too.
However that was the first generation of Li-Pos. Later ones were not so volatile and would usually only get as far as the swelling stage with no pyrotechnics and not ignite or smoke when stabbed..
Lithium-ion is of course a completely different thing and we are also well down the line as far as the "White Heat of Technology" is concerned, so I would say that if they are sold for Motorcycle fitment, then the conventional charging system should be okay unless stated by the battery suppliers to the contrary.
However a reg/rec failure or short circuit still carries the risk of a fire. A rather hefty fuse would protect against most shorts, but for protecting against charge surges, perhaps a BEC (battery electronic control) might be the thing.
On a model a BEC is used to prevent the battery from discharging below a threshold voltage (from which it will not recover). By shutting off the current to the motor, allowing the radio and servos to still work to glide to a controlled landing.
I am sure that a BEC with a "High" threshold should be possible to make or even already be commercially available?
StevieL is a bit of a wizard with electronics...He might be your man..
