Integrated vs replaceable batteries.

[Lance_Wallen]

I posted this over in the APV forums... probably should have put it here first.

I'm working on finalizing my design and I'm down to one last (I think last) decision to make...

integrated vs replaceable batteries.

I'm going with a DNA 12 board and they have those nifty charging circuits you can get. When penciling my design I can get my size down a little bit by actually going with an integrated battery. The plan is to use 2 18350s in parallel for ~1500mAh (depending on the cells I buy, have to be IMR). The other option is to put terminals in there and a door so I can replace the batteries.

my current daily vape is a provari with a 1600mAh 18650 in it. The battery lasts me all of a day and a small part of the next day on a full charge so i figure a 1500mAh should comfortably last me a full day without access to a USB port and I generally have my USB battery pack with me for my cellphone/tablet just incase I use em a lot for osmething and they get drained.

Just thought I'd get other peoples thoughts on integrated vs replaceable before I made the final decision, I'm kinda leaning towards integrated but I know back in the day when I was picking provari vs darwin one of the biggest selling points was the replaceable battery in the provari... just dunno if that's still considered a "big deal" so to speak, assuming you have enough juice to get a days vape out of it.

 

[asdaq]

If it is easy to add and actually gives you a smaller package, then I would choose intergrated. For mine, I would not have either of those benefits so I build removable. I really try to keep the electronics as small as possible, and there is no room for a charging circuit and plug. As an alternative, I try to make changing batteries and other disassembly easy and 'fun'.

You could ask the same question regarding your cellphone: would you rather plug it in to charge or remove the battery every time?

 

[slimest]

I usually make e-cigarettes with integrated cells. Contemporary charging boards are small enough, micro-USB connectors are small too. Example of such design: http://www.e-cigarette-forum.com/fo...ck-boost-stick-based-happy-vaper-booster.html
Please look to charger - it's really miniature after some redesign.

 

[asdaq]

Slimest, I see you got it 14mm round, how thick is it with the diode still intact? And how big is the micro USB plug assembly? Sigh, this looks tempting, but then I would need to switch to SMD caps to get a little more free space. And I stocked up on some mini pushthrough 16v caps...

 

[Lance_Wallen]

well, adding the posts for the batteries in the box adds 3-5mm on either side of the batteries as opposed to just soldering on some nickle tabs and leads. Adding the battery charger board adds 0 to my dimensions because it'll fit in the void space Ive got for wire runs. Theres benefits to designing and machining your own enclosures

 

[jimbalny]

Is it really as dangerous as people say to solder tabs to li-ion's?

 

[Lance_Wallen]

Well... it's not if you do it right. I just wish I could find some 18350 IMRs with tabs on em already so I didn't have to deal with it adding that kinda heat 'can' cause a problem but if you do it smart you'll be fine. I'm tinning the tips one at a time then going back and connecting the wires so I never have that much heat at a time.

 

[jimbalny]

Do you use a temp-regulated iron? What do you think is a good setting?

 

[Lance_Wallen]

nope, I just use an ol school iron. I'm just gonna get it 'hot enough' to melt the solder, tap the sponge to cool, etc.