Sorry to ask a dumb question but I am relatively new to the forum. I am confused about battery types and what can be used in what. I know AAA/AA/C/D batteries but in the forum I see flashlights that use such batteries as 18650 and other numerical descriptions. I am in the US. Can the “alphabet letters” batteries be used in place of them, or is this a different size/shape, etc? Is there a place I can look this info up? Thanks so much and I am sorry for asking such a simple question. Ed.
Usual the "numeric" batteries are LiIon batteries, they have much higher voltage than alkaline batteries, it is about 3 times higher.
The size is also different, a 18650 battery is about 18 mm in diameter and 65 mm long. You can find LiIon batteries that have the same size as alkaline batteries (10440=AAA, 14500=AA), but due to the voltage difference, they are not directly replacements. There is a few exception, some lights will work with both alkaline and LiIon, but not many. A light not designed for LiIon will usual die if you put a LiIon battery in it.
On my website you can find a couple of articles about batteries and a lot of battery reviews, but I have not really written something comparing LiIon to alkaline.
Li-ion batteries list there dimensions in there label. 18650 means 18mm diameter and a 65mm in length. Li-ion 14500 means 14mm diameter 50mm length this is also close to the same size as a AA alkaline battery. It might fit in the same place AA will but their voltage’s are very different. AA’s are 1.5v Li-ions are 3.7v nominal and 4.2V fully charged. So you can see if you stuck 2 14500 Li-ions in your TV remote control where its expecting 3.0v total, how this could be a instant smoking problem at 8.4v total.
Thanks to both of you, wow, am I glad I asked that question. Thanks again, Ed
The most common 18650 battery will be a Lithium Ion (Li-ion) rechargeable battery, and not disposable until many charges. These batteries are commonly found in laptops, with six or more of these cells inside a “case”.
These li-ion batteries come in “protected” and “unprotected” varieties. It will be dangerous to let the cell voltage get too high, or too low. Protected batteries have electronics built into each cell to stop voltage from being too high or too low. Unprotected cells depend on the user to determine when cell voltage is too high or too low. Danger could encompass fire, explosion, or noxious chemicals. Make sure you read up on safety before you use these batteries.
Li-ion batteries are found in laptops, cell phones, tablets, etc. All with good safety records. But these are engineered situations that control the voltage. A person using these cells in flashlights needs to take that control responsibility. For one thing, a flashlight taking more than one 18650 cell is best used with “matched” cells. Matching means the cells are operationally comparable.
Some good reading to start:
Wow, I can see I am really out of my league with those. I almost ordered a flashlight that took them and I can see that would have been a huge mistake for a novice. I was going to ask where you buy those batteries as I don’t recall seeing them in places like Home Depot or Lowes, but I could be wrong, anyway I don’t have to ask that now, I am sticking with my little AA batteries from Walmart. Thanks again, Ed.
Didn’t mean to scare you. Consensus is that a protected Panasonic 18650 with a good charger will serve you well. Just understand what the ball game is.
Charger:
Some debate here. See some of HKJ’s reviews.
I will also say: Do not get scared about 18650 batteries.
In my opinion they are some of the best batteries around (That is probably also the reason that nearly every laptop computer uses them).
There are a few rules you need to follow:
1) Use quality batteries (Like Panasonic).
2) Never over discharge the batteries (Use protected batteries and you eliminates that risk).
heh heh heh…I think every one of us thought the same when we first started …….It’s only a matter of time til you give in and go Lithium. Just read the rules about their use.
I was in your shoes about a month ago; I started out with junk Ultrafire 18650s (DO NOT get this brand) in a combo deal with an 18650 flashlight. I only just got a good pair of panasonic 3400mAh 3.7v protected 18650 (Wilson linked these above). I took them out on a fishing excursion and they are absolutely amazing. Used the light on Turbo off and on throughout the 9 hours on the water and the batteries dropped about 15% charge. Where I would have had to replace the batteries in my 3x AAA light at least once. [Edit: If I acquired the rechargeable a few months ago they would have already saved me more money in the cost of AA’s and AAA’s I had to use in my headlamp/flashlights than what I spent on flashlight/charger/18650 batteries. Went night fishing pretty much every single weekend since the end of May]
I’m actually thinking of converting to all rechargeables pending the outcome of a few more trips.
If I were you I would spend a couple hours reading about the batteries, and possibly spend $40-60 on a Li-Ion battery/charger/light to try it out!
Living in Canada it costs a lot to buy Samsung 30Q 18650’s here at vape shops. Batteries that I have bought from local stores seem to be genuine and I have no complaints (other than the cost) My question is, are the Samsung 30Q’s sold from bang good and fast tech genuine? They are wrapped differently in the pictures than the ones that I have. The price is much better so I am interested. Any experiences with either sellers and their samsung 30Q’s or other 18650’s and 26650’s?
Thanks so much
…Are all trusted and well regarded vendors on this site, and others. All of them state their cells are tested and guaranteed against fakes. I have dealt with all 3 over the last several months and been very pleased.
Thanks for your reply. The Canadian dollar is really weak against the US dollar so we pay close to 1.30 CDN for 1.00 US dollar. Add on the almost 20.00 shipping, the taxes and duties at the border and it is close in price to buy them here in Canada
I bought several samsung 30Q and sony VTC4 and VTC5 from fasttech, if the title or description says it’s an authentic, you can buy with confidence. A bunch of vapers are buying their batteries from fasttech and you sure don’t want to blow your face with fake that can’t handle high load. Never seen an accident reported to fasttech due to fakes with “authentic” batteries. Won’t hurt to check the discussion threads and reviews on fasttech to know what people who bought it have to say about a product.
Thanks so much