Hi! Maybe I can help. I started with a Joye 510.
First thing is that there is no such thing as a cigarette sized e-cig that will last all day, or anything close to it.
The Joye 510 batteries range from about 180mah to 480mah, IIRC (It's been awhile).
You can figure roughly 1hr of vaping time per 100mah of battery capacity. It varies somewhat according to your vaping "pace".
Also, the little batteries begin to wear out fairly soon and that 1hr. becomes shorter and shorter as they age.
So, if you're looking for something that lasts all day, you're going to need something a bit larger, maybe the size of a Sharpie marker or small cigar.
The "mid-sized" e-cigs accept a cartomizer (cartridge) that can be refilled. The standard procedure with them is to buy blank cartomizers and fill them with liquid (juice) that you buy separately. The best juice is usually made and sold by a separate company than the ones that sell e-cigs and hardware. (but not always).
Also, the mid-sized e-cigs usually come in pairs so that while one is charging you can use the other one. You should never recharge a battery overnight. You want to be around if something should go wrong. These batteries are lithium and the potential for overheating or even catching fire is remote, but it does exist.
There are a couple particular models that have been time tested to be extremely good for new vapers. They are full powered 3.7 volt e-cigs. They have capacities around 1000mah and should last you all day, or very close to it.
They accept a wide variety of cartomizers and other attachments to hold your juice and deliver it to the vaporizing element.
I'm going to recommend two models. They are very similar except that one takes replaceable batteries, like a flashlight, and one uses a battery sealed within the unit. The one with replaceable batteries also accepts a very large battery that is available in up to 3100mah, so that would last you at least 2 and maybe 3 complete days between recharges. However, a larger battery is bulkier than a smaller one, so it's up to you how compact an e-cig you'd want.
Here is the kGo. It is 1100mah and comes in a kit with two batteries, a charger and blank cartomizers (cartridges)
You can get it many places. This is just a representation.
http://www.sweet-vapes.com/shop?page=shop.browse&category_id=31
The one that takes separate batteries is here: It takes a 1050mah battery or, as with the model in this link, it takes a larger battery that is usually about 2000mah as supplied in the kit. It will include a charger and 2 batteries. There are other colors available and it also has a switch that can be replaced if it breaks.
E-Power
You can't go wrong with either of these units. They're reliable and time tested. If you look through this forum, you'll see many good things said about both of them and they'll both do exactly what you're looking for
Or, maybe some Silvangelism?
