Ive been reading about batteries for the last hour and I am more confused than ever. I have almost a dozen 18650 lights that I would like to have decent batteries for.
I also have a 3 dollar ebay charger.
1.What is a good battery with decent run time. It need not be the best as i need a bunch of them but better than the “energy” and “ultrafires” from ebay.
2.Is my charger satisfactory or will it ruin batteries?
I use a bunch of different batteries. Panasonic pf have been my favorite of late though. Good power with decent mah rating and fairly cheap. Get a better charger though.
I use an xtar wp6ii. I charge a lot at a time. Someone will suggest a better one I’m sure.
I’ve had good success using the I4 Intelichargers, the Nightcore brand is decent and its a smart charger, so it can be used for various battery sizes like the 18650 or just a AA etc. I see them selling for around $17. I wouldn’t use a $3 eBay charger, but I won’t use cheap “**fire” batteries either.
I get my batteries from various sources, but I tend to favor Panasonic 3200 and 3400 18650’s that are protected. As far as I know these are a good choice from a US vendor if your lights can take the long suckers: NCR18650B
I like C-8 lights and I use my Tangsfire C-8 as a bicycle headlight with the protected Panasonic 3400’s for the best run time. But, any name brand cell from a legit vendor will work fine, if they are cheap in price, look at them closer, lots of junk out there. I’ve found I’m better off just ordering from a vendor in my country with a good rep, I’ve gotten DOA crap from FT after waiting a long time to get them. I just get batteries from mostly premium vendors now, but sources like BangGood could be worth the risk on small orders when they have good deals on quality batteries. Just harder to get them via air mail these days.
Nitecore and Xtar branded chargers are excellent choices. Either manufacturer tend to make their chargers with a whole bunch of features. It’s just a matter of checking what they have and which features you want.
As for the cells, I’ve got these NCR18650BE protected cells on their way (20 of them). I have bought from this seller previously, but you have to wait a while for them to get to you. I have also got the unprotected version of this cell and seems to power up my lights just fine. The link provided, I think, provides one of the best $ per mAh offers out there.
Depends on what you want the cells for. Typically, higher drain rate cells have a bit less overall capacity than lower drain cells. For a max hot rod DD light generally some type of IMR will supply the most current but for longest run time at a more moderate current another cell chemistry would be better. “Best” depends on usage.
You haven’t said where you’re from, but the good English makes me assume American so…
Panasonic NCR18650PF’s are a good cell for you to start on. Not the most expensive, but high capacity and they’ll work well in some more high-drain lights as you start to mod.
One rule for Li-ions though, use unprotected cells in series only if they’re from the same batch/lot/order, and have the same number of cycles on them. It also helps to have low voltage warning, but we can cross that bridge when we get there.
NightCore i2 or i4 and believe it or not laptop pulls are MORE than enough for GP use (sub 5A continuous, most average lights run 3A~ continuous or lower)
Most laptop pulls are decent high quality, have sufficient enough life left in them and can be had for dirt cheap (several members here sell them for very cheap) they should be checked though, you can get some that are damaged or at end of life service, but still MUCH better than the **fire junk found on ebay
The super cheap Chinese charger shouldn’t be trusted
If you are into DIY, you can build you one out of a TP4056 charger board and a battery holder
Here are a few links that are always beneficial
I don’t charge a lot of cells at one time, so I’m very happy with my Xstar VP2 (review) which is considered one of the best for li-ion batteries.
Only an hour! You’ve barely even started 
I would definitely not be using a $3 ebay charger. As others have already said, get yourself a Nitecore i2 or i4 charger.
If I was you I would get some decent cells like Panasonic, Samsung, or even Sanyo. I once bought the Trustfire/Ultrafire batteries and eventually replaced all of them with Panasonics or Samsungs, if I had just spent the money on the good ones to start with it would have been cheaper in the long run.