Inexpenive and quick 5 volt mod

[DoubleD]

I made a 3.7 volt laser mod and really liked it, but wanted to try a 5 volt mod also. I wanted something similiar and knew that the required electronics would not fit in a laser mod, so I looked around and found that MadVapes also had the laser which accomodated 2 AAA batteries, at a cost of $5. I have tinkered with flashlight mods over the years and had a good supply of rechargeable NI-MH batteries (1.2 volt AAA size) rated at 1800 mah. So why not insert 1 of the NI-MH and 1 10440 protected lithium and get a total of 5 volts, I thought.

I modded with a 510 connector in the top cap and drilled a vent hole in the bottom cap (for safety) put on a Boge Tech carto, inserted the two batteries and away I went. Initial voltage on a fresh load is appx. 5.5 volts but it levels off to 4.96 pretty quick.

After about 2 hours of pretty heavy use I noticed that the vapor was falling off so I opened it up to check the batteries. The 10440 was holding at 3.8 but the NI-MH had dropped to about .7 volts. I inserted a new NI-MH and the original 10440 and I was back in business. 2 hours later it started to fall off again and at this point I inserted 2 fresh batteries.

The vapor is awesome and if you don't mind the extra length, it is quite small. I use it at the house and in my shop because it is so much better than the 3.7 mod.

Very inexpensive to make and it preforms just like a passthrough.

Two of my friends are hounding me to make one for them, so I better get busy.

Here's a couple pics.

DD

 

[WillyB]

Mixing different chemistries is always advised against, even the same chemistry using old and new cells.

 

[bigoted]

Nice 1 congrats ^^

 

[Nobodyatall]

Ahhhhh..... Be careful with that. You could damage the NiMh if its voltage drops too low. A reversed polarity can kill'em if I am not mistaken. Nice find for those with a taste for some risk. I'm not one of them for that combo.

 

[NoLeak]

When you mix Lithium Ion batteries with other types of batteries you no longer have a mod.

YOU HAVE A BOMB.

More precisely a firebomb.

Protected cells or not. Just don't do it.

The following needs to be said IMHO. It's not at all directed at DoubleD personally.

People shouldn't be using loose Li-Ion cells in series at all, even with other Li-Ion cells. Parallel is kind of ok provided you take care to match the cells. Use a booster if you absolutely have to have 5 volts.

If you aren't to the stage in your electrical experimentation where you know "series", "parallel", and "cell matching" then think about using some good quality NiMh cells instead.

Sanyo Eneloops perform great in high current applications. Three AAA work very well for our purposes and last much longer than you'd think. Hit up Amazon and check out the Eneloop starter kits. They're inexpensive and come with good chargers.

When electrical engineers design something that uses series combinations of Li-Ion cells they put a lot of extra stuff in the battery pack to ensure safe operation. That's why you nearly always see 3-4 terminals on Li-Ion battery packs. Only two are needed for the power. The others terminals are connections that allow the smarts in that battery to talk with the smarts in the device and charger. All of that really is needed. The end cap protection circuits inside these loose Li-Ion batteries are not an appropriate substitute.

 

[WillieB69]

When you mix Lithium Ion batteries with other types of batteries you no longer have a mod.
YOU HAVE A BOMB.

Sweet.... ECF is an illegal terrorist organization now.