battery run times 8 AA versus 1 9V/ 2 AA?

[runewolf]

Fishing for someone with experience in both before I try to reinvent the wheel. Disregarding space requirements for two 4AA battery holders versus 1 9v and 1 2AA holder, how would run times compare between using 8 AA's to give you 12V to using one 9v and two AA's for running a 12V fan like this one-----------

Edited March 24, 2022 by gmrhodes13
link removed no longer working

[kiyotei[TK]]

YES!!!! Run the 8 AA rechargeable batteries. The 9volts have a very short life. You get maybe 2 hours out of them running small fans. You get a lot more fan time and amp time using the AA batteries. The 3 extra volts also gives everything a bit of a boost. I find you can mount the two 4 battery packs in the the curved rim of the helmet and wire them in series using the snap connector. Make sure you check your wiring so you don't accidently reverse the power to your amp. I'll post some pics with I get to it. Yes the 8 AA's are heavier but the battery life is well worth it.

[runewolf]

YES!!!! Run the 8 AA rechargeable batteries. The 9volts have a very short life. You get maybe 2 hours out of them running small fans. You get a lot more fan time and amp time using the AA batteries. The 3 extra volts also gives everything a bit of a boost. I find you can mount the two 4 battery packs in the the curved rim of the helmet and wire them in series using the snap connector. Make sure you check your wiring so you don't accidently reverse the power to your amp. I'll post some pics with I get to it. Yes the 8 AA's are heavier but the battery life is well worth it.

 

Thanks Jim, I gave up on anyone replying to this, so I've been testing it out this week. I have over 8 hours run time on two fans using Duracell AA's. The setup I am using has two 4 battery holders that hookup using a 9v connector. I'm still playing with where to put everything in the helmet so I can easily take it off and on. But otherwise I'm pretty happy. I have everything using velcro right now until I decide on something more permanent.

[MiDri]

Thanks Jim, I gave up on anyone replying to this, so I've been testing it out this week. I have over 8 hours run time on two fans using Duracell AA's. The setup I am using has two 4 battery holders that hookup using a 9v connector. I'm still playing with where to put everything in the helmet so I can easily take it off and on. But otherwise I'm pretty happy. I have everything using velcro right now until I decide on something more permanent.

 

 

AA Rechargeable go up to about 2500mAh (this determines how long the battery will run)

AAA are about 900mAh

and a 9v is about 400-500mAh

[tk-trooper[TK]]

I'd sure like to see how you have this hooked up.

[runewolf]

I'd sure like to see how you have this hooked up.

 

LOL, you want to see my poor wiring skills?! I put it together very quickly late in the evening so instead of doing it all nice and color coded like I should have it is pretty bad. I'll see if I can get some pictures that make sense tonight. I'll take one of inside the helmet and then pull the wires out of the wire guide tubing and show the entire unit with both fans.

[kiyotei[TK]]

Hey MiDri thanks for posting the mAh ratings. I'm sick this week and didn't have the energy to look it up again. With today's battery chargers using 8 AA batts is a great way to go. The cheap chargers today show you when they are recharged, don't over charge the batteries, and charge them quickly.

[TKDUEUNO]

Dump the 1.2v rechargeables and switch to lithium 3.7v batteries. Much lighter, super long lasting.

 

I run my ROM/FX with three of them for over two days of trooping, almost full volume, only 900 mAh.

 

I use these, but there are also higher mAh.

 

Three of them also for fans, you get 12v at full charge.

[MiDri]

Dump the 1.2v rechargeables and switch to lithium 3.7v batteries. Much lighter, super long lasting.

 

I run my ROM/FX with three of them for over two days of trooping, almost full volume, only 900 mAh.

 

I use these, but there are also higher mAh.

 

Three of them also for fans, you get 12v at full charge.

 

Nothing like putting an explosive next to your head!

[TKDUEUNO]

Those are not the dangerous LiPo, they are LiIon, the same lithium type batteries used in cell phones.

 

You have it in your pocket all the time.

[kiyotei[TK]]

Nice find. I may have to upgrade mine to these. With ROMFX you have to make sure you don't exceed 12 volts. I got the ROMFX amp as well. I could use three of those batteries in my helmet. That would cut weight. I would have to make sure I can find battery holders that work with them. They might be fatter than standard AA batteries and not fit in that type of holder. I had this problem with another set of rechargeable AAs I bought for my Rock Band guitarre. The batteries wouldn't fit in it.

[TKDUEUNO]

If you buy protected ones they are slightly longer, but they fit standard holders no problem

The diameter is the same as regular AA.

[kiyotei[TK]]

Here is a link to my photos showing how I have my battery packs installed. You can also see my ROMFX and fans. A note on the fans. I cut slots in the back of my helmet which the fans sit over. They draw in cool air and blow the air towards the front. I'm using 2 squirel cage fans. They work really well. I have comments under each photo explaining what you are seeing.

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Edited March 24, 2022 by gmrhodes13
link removed no longer working

[tk4619]

I would recommend looking at using 5 volt fans, yes they do make them, rechargeable batteries are only 1.2 volts as compared to 1.5 for regular ones. with less voltage the fans will actually draw more current to make up for the voltage drop of the rechargeable ones. Also with a 9 volt you get less amperage out of them.