It did hurt, but it was totally worth it. Now I have 6 18650 batteries and I have tried them in my PD35. Works fine!
Keep in mind that 18650s from a laptop battery are likely unprotected cells. Be careful to not let them fully drain, yadda yadda... Sent from my iPhone 5s using Tapatalk
18650 batteries have higher density, so they're able to deliver higher amperage, for longer periods, and they do it far more efficiently than a pair of CR123s is capable of delivering. As an added bonus, because they're rechargeable, they're far more economical, in the long run. But don't skimp on a good 18650 battery (a Panasonic based 18650 is the best bet. And don't forget a decent smart charger). Just be careful and read up on the proper care and safety considerations to be considered (when using 18650's) and you'll be good to go :-
Quoted from a thread on CPF: Re: Protected vs. Unprotected 18650's Protected cells have a circuit that protects the battery from over charging, over discharging, and getting too hot. If something bad happens, the circuit opens--and you'll see zero volts across the battery till it's plugged in a charger. These are what you want. Unprotected cells are just raw batteries. In lithium batteries, this is good for people who know what they are doing and are trying to push the envelope as far as super high discharge. To the average Joe, this can result in fires or even batteries exploding so violently, they burst your flashlight. If you have to ask--stick to protected cells. Sent from my Retina iPad Mini using Tapatalk
Higher voltage, more durable and reliable output, rechargeable. I would say to buy them online for $10-20 instead of salvaging marginal cells from a laptop battery. If you are going to use them, just be careful . Edit: If one of the casings is ruptured it's also possible to ground out against the side of the light body and as they said previously explode.
