Total noob (and I did read through threads!)

[Forgetful Jedi Knight]

If he wires 2 AAs in parallel to extend run-time, repeat that for the other 2 AAs, and then wires those two packs in series with each other, he would have a 3V setup with twice the run-time of a normal AA.

I'm pleased to see that you think that every new person here is an electronics and wiring genius.

[Bark]

I'm pleased to see that you think that every new person here is an electronics and wiring genius.

Did you read JediCarpet's 9th post in this thread, FORGETFUL Jedi Knight?

[Forgetful Jedi Knight]

Did you read JediCarpet's 9th post in this thread, FORGETFUL Jedi Knight?

Yeah, I read it. And IF the holder is not "re-wired", or done improperly, she will be getting the 4.8V and maybe a blown LED if not resistored properly - bad for those on a tight budget. 2.4V won't be enough for the Red LED she wants to use, without under powering it.

Assuming new people will or can do things can be a bit dangerous.

Let's keep it moving before I magically remember where the cleaning tools are.

[Forgetful Jedi Knight]

I definitely understand that, the rechargeable battery is just a bit expensive right now and I have a bunch of rechargeable AA's at home already. Since I'll only be using the light saber a bit when I cosplay, I don't think the batteries will be too much of an issue.

Be aware that rechargeable AA's are only 1.2V per cell, so with 4 cells you would get 4.8V. You wouldn't be able to "double your runtime" as suggested, because 2.4V wouldn't really light up your LED too well, and I don't know that your batteries would be able to output enough current if you tried Jedi Carpet's little trick.

When you redo your resistor calculations, plug in 4.8V.

[Bark]

Yeah, I read it. And IF the holder is not "re-wired", or done improperly, she will be getting the 4.8V and maybe a blown LED if not resistored properly - bad for those on a tight budget.

Assuming new people will or can do things can be a bit dangerous.

Let's keep it moving before I magically remember where the cleaning tools are.

While I certainly advocate safety and appreciate the skill involved in making a 4-AA Cell, 3V battery pack, it is what the original calculations were based on. I do make an assumption that those wanting to construct a light saber from scratch have (or is eager to learn) the electrical skills necessary to accomplish the task. (I don't think I'm the only one. It wasn't even my idea.) To hopefully keep this post on point to the thread, ginamarie72 will need to decide on a definitive battery solution first.

#1. Four alkaline non-rechargeable AAs wired in series at 6V
Pros: Probably easiest for a newbie
Cons: Limited run-time (probably very limited)

#2. Four alkaline non-rechargeable AAs. Two sets of AAs wired in parallel with both sets subsequently wired in series at 3V
Pros: Batteries can be purchased everywhere. Double the run-time (still limited compared to lithium ion)
Cons: Tricky wiring of a battery case will be needed. Need to know the difference between series and parallel.

#3. One 3.7V lithium ion
Pros: Longest run-time. Future upgrade to recharge port possible.
Cons: Unprotected cells can be dangerous, especially for newbies. Batteries not as widely available as AAs.

#4. The rechargeable 1.2V batteries wired in series
Pros: Seems to be the OP's preferred cells.
Cons: I have to imagine run-time will be limited.


If it's worth anything, I think option #3 is worth investing in for the extended run-time.

[ginamarie72]

I decided to go with AA's and ordered this 4AA holder. To be honest, my dad told me to not worry about the resistor and battery holder. He's a computer engineer, super electronic savvy, wiring genius (he's pretty darn awesome). For example, I once had a computer presentation to do in 6th grade on binary and he helped me make a box with lights and switches to illustrate how binary code works. So if what I get battery-wise doesn't work well, he said we'll just use something he has. I was talking with him yesterday and he started talking about some device he can hook up and test all the electronic stuff and my eyes sort of glazed over. I think he is actually excited by this project! I *hope* I got the exact perfect items just to feel like I made him proud, but if I didn't, it isn't a big deal. As long as I got a good LED and the parts that go with that, I'm solid.

I think I mentioned that this saber will only be for a few cosplay events currently, so if I feel the need to upgrade the battery I'll do so. Regardless, everyone here has been really helpful and I'd love to show off what we come up with when it's built. I just got the email that my order has shipped, so I am super excited.