Can you mix a single Lithium Ion and Nickel MH Battery to power a saber?

[Shady Canuck]

Just wondering if anyone has every tried mixing a single 3.7V Li-Ion and a 1.5V NiMH battery in a AA battery holder in order to get a combined output voltage of 5.2 volts? I know these two types of batteries have different recharging requirements & types of chargers, but I wondering if the discharge rate is stable if you were to mix them?

I'd like to try running an Ultimate FX sound card off of 5.2V (they can normally handle between 4.5V and 6V), but I want to make sure that the Li-Ion isn't going to explode or anything, lol. Thanks in advance for any feedback or advice you can provide.

[Forgetful Jedi Knight]

Mixing battery types is NEVER recommended for this hobby. If you want to use a sound card like that you could use 4 AA NiMh batteries, that would give you 4.8V.

[Silver Serpent]

No. Never mix battery types. They'll have different discharge rates and possibly lead to leaking at best, or fires/explosions at worst.

It would be better to use two li-ion batteries and a 5v regulator.

[Onli-Won Kanomi]

Agreed on NEVER mix battery types.

For your application another option would be a 4x AA holder with one dummy cell + 3x AA alkalines for the 4.5V you want. There are also some 3X AAA holders that small flashlights use to power small 3-5mm LED arrays but AAA batteries do not provide much mAh capacity for the high power LEDs we use in this hobby much less soundboard and speaker current draw so are not ideal for anything more than a simple stunt.

[Shady Canuck]

That's what I thought. But thanks for confirming my suspicions, guys.

Any ideas on what kind of 5V regulator one would use on two Li-Ion batteries (combined voltage of 7.4v)? And is it sold by TCSS? My only concern is how hot it might get. I'm starting to think I might be better off with a 4 NiMH battery solution.

[Silver Serpent]

I've used a simple 5v regulator from Radio Shack, model 7805, in my builds that require the use of one. It doesn't have any major heat issues with a source voltage of 7.4v.

[Shady Canuck]

Thanks for the lead on the Radio Shack 7805 regulator. I'll look into it.