The charging cable plugs into the camera. So the battery has to be in the camera to charge it. What I did was charge the first battery in the camera and once it was charged swap it for the other battery and charge that one. Hope this helps. 

Yes, it comes with two batteries and a charger for the batteries. 

Dear Customer, as long as it has a 1/4 standard screw mount, the cannon rebel t7i could fit this tripod. 

K&F Concept camera tripod you are asking, yes, you Canon rebel sl2 could be used on our tripod. Your camera could be used as long as it has a 1/4" standard screw interface; If your lens is large or telephoto zoom lens, please ensure to expand the leg angle, and hang some weight to the hook to increase its stability. For camera with telephoto zoom lens, you need to buy a tripod mount ring additionally for better balance.The center column also has a hook to hang weight on to lower the center of gravity on this tripod to make it more sturdy and less prone to vibrations which is awesome for photography where you take long exposures . 

hello ， the AI to EOS adapter ring i ssuitable for nikkon AI Mount lens and canon camera body. so you need to confirm your sigma lens specific mount . We care about our customers, any questions, you can ask us directly at gearfocus@kentfaith.com. All emails would be replied in 24 hours, no exception.