LED high power emergency lighting solution

[Biffo]

The problem with running them in series will be the same as your old Christmas Tree lights ie if one goes faulty -they all stop working- then its hunt the faulty one.
far best to run them in parallel with a good current supply.
In the download section at the top of this page there is an excellent electronics calculator for looking up your ratings

a typical emergency charging circuit
http://www.circuitstoday.com/automatic- ... ency-light


If your running off the mains then all you need is a relay that makes contact (rather breaks contact) when the power is lost to feed into something like the circuit above