Re: E-99 won't fire
Even though you fully charged the battery, it may be bad. Sounds like the 'noid isn't pushing out enough power to trip the sear. I would get a new 9.6v rechargeable and see if that works. Make sure its a 9.6v rechargeable battery, if its not it will not work.
You might also want to take the marker apart and make sure the striker isn't stuck and that it is well lubed and very of any dirt.
Try that and let us know.