is there a reason for the shape of mods?

[bssage]

It seems that most box mods make use of the longer more slender batts where the tubes make use of the short squat batts. This may be a stupid question. But is there a technical reason for this or is it just a matter of convenience?

I am thinking about making a box mod that uses 15270 or 123 or similar.

also all the mods I have seen limit themselves to two batts. Again is there a reason for this?

 

[Dalton63841]

Just that most box mods are built with AA or AAA battery boxes, which are readily available and easy to find and work with. As far as the number of batteries, if they are in series, its a voltage thing. In parallel it doesn't matter, just however many is convenient for size.

 

[CraigHB]

It's actually not a good idea to run Li-Ion batts in parallel. You can get over-current condtions if one is low and the other is not (one charges the other without bound). It's possible to run Li-Ion batteries in parallel safely with properly engineered cell monitoring and protection circuitry, but for casual modding, it's best to avoid it. If you want to run batteries in parrallel, it's much safer to use NiMH bats that don't have the volotility of Li-Ion batts.

Otherwise, mods with two Li-Ion cells are typically running them in series for higher voltage, either regulated or unregulated. Even then, it increases the risk of battery issue since there's the possiblity of high currents occuring in a battery that's discharged. When using series batteries, always match the cells and take them off the charger and put them in the mod in pairs. There should be a way to quickly and easily disconnect the batteries (such as master switch or quick release) if there is a problem of some kind. Never put Li-Ion batteries in a sealed enclosure.

Battery size and shape is generally a matter of preference revolving around form factor and battery capacity. It can also be a matter of safety. For example, running two LiFePO cells in series is much safer than running two LiCo cells in series. The safest configuration is a single battery. There are off-the-shelf boost modules you can use to run higher voltgage which is preferable to using multiple Li-Ion batteries.

 

[mwa102464]

It seems that most box mods make use of the longer more slender batts where the tubes make use of the short squat batts. This may be a stupid question. But is there a technical reason for this or is it just a matter of convenience?

I am thinking about making a box mod that uses 15270 or 123 or similar.

also all the mods I have seen limit themselves to two batts. Again is there a reason for this?

Size would be my guess, no one wants to be vaping from a huge box or tube and size is the major concern, so fitting in one 18650 with a booster so you can achieve higher voltage or using dual batts whether stacked or side by side it all comes down to size. I would love to see more mods coma out using one 25500 or even dual 2 x 25500 Batts side by side myself and compacted as small as they could possibly get the Mod. I would also love to see when batt technology gets better and if they can shrink the size of batts and get the same power we achieve from them now then Mods would get even smaller and that would be great.

 

[CraigHB]

I built one myself with a 5000mAh LiPo battery, runs a week between charges, it's not that big either, about the size of a pack of 100 cigarettes, a bit thinner and wider. As far as energy density, don't hold your breath. It's taken decades to get the energy density as high as it is now. These batteries already hold so much energy they're explosive. Imagine tripling that. You'd need a bomb shelter to charge them. Hehe, it reminds me of that scene in Terminator 3 where the T-800 (Arnold) throws his damaged battery pack out the car window and we see a small nuclear explosion.