Voltage converter

[ujiro]

Hey guys

I was wondering if anybody ever thought of using a voltage converter/regulator in airsoft. When a battery is fully charged it gives sweet voltage, and thus awesome RoF.

I was thinking, if one used a voltage regulator, for say or 11 or 12V (the average range of voltage on a fully charged 9.6V battery), they could maintain this voltage, and thus RoF and trigger response, the entire time, regardless of the charge of the battery.

The only issues I can see is perhaps over draining the battery by shooting near the end, but I don't think that would be an issue.

I theorize using this with my battery, which is a 9.6V 4000mAh, so I barely use any of its capacity in a days gaming, since upping the voltage would theoretically (and quite obviously) use more capacity.


Anybody's thoughts? Is there some concept I am just completely missing here as to why this idea might fail?

[ILLusion]

Your concept of electronic physics is skewed.

It's physically impossible to "suck" voltage out at a constant 12v.

CURRENT (or Amperage or "A") can be pulled or sucked. It is NOT pushed by the power source.

On the other hand, VOLTAGE is pushed through the circuit. Voltage is NOT pulled by the load. That's just not how it works.

If the power source isn't PUSHING out 12v, you can't pull 12v out of it.

The only way to push 12v out constantly throughout the entire charged life cycle of the source is to actually use a 12v battery and install a regulator to prevent the power from exceeding the 12v and cut off when the power drops below 12v.

[ujiro]

Umm... I disagree? Step-up voltage converters exist..

http://en.wikipedia.org/wiki/Boost_converter

Read the applications part. The Prius uses this concept to run its batteries at a constant voltage.

[mcguyver]

Voltage converters require power to step the voltage up. Thus, they are also a consumer of the precious current your battery has stored to run your gun.

Complete waste of time.

Best to get a 12V battery if you want 12V. BTW, the 12V you may read on your battery with a meter will drop almost instantly to it's designed 9.6V when load is applied.

[ILLusion]

Oh, if you're referring to a SMPS, then sure... but all of the ones I've seen were the size of...... a computer power supply and weighed like a brick. I'm not sure where you'd store that on your gun or whether it's even worth carrying that extra 8 pounds of electronic gear.

Also, like mcguyver stated, you end up using some of the current to operate the regulator.

[ujiro]

I realized upon saying it, really what I meant was, keep it at the proper voltage when fully charged. Because you can hear a relatively distinct different in the rate of fire and whatnot of a freshly, fully charged battery, and one that has been used for a little bit.

Originally Posted by mcguyver

Voltage converters require power to step the voltage up. Thus, they are also a consumer of the precious current your battery has stored to run your gun.

Complete waste of time.

Best to get a 12V battery if you want 12V. BTW, the 12V you may read on your battery with a meter will drop almost instantly to it's designed 9.6V when load is applied.

[mcguyver]

Originally Posted by ujiro

I realized upon saying it, really what I meant was, keep it at the proper voltage when fully charged. Because you can hear a relatively distinct different in the rate of fire and whatnot of a freshly, fully charged battery, and one that has been used for a little bit.

You can't keep the voltage up. It's called drain, and all storage cells experience this. You could try it, but it follows a geometric pattern.

Your best bet would be to pack around 20 AH of batteries on your back, and connect your gun via external wiring. The more discharge capacity you have, the more stable the current flow and the less noticeable the drain is.

I know what you're asking, and unless you have a source of power generation (like a mini nuclear reactor in a backpack), it's not really possible.

[ujiro]

Originally Posted by ILLusion

Oh, if you're referring to a SMPS, then sure... but all of the ones I've seen were the size of...... a computer power supply and weighed like a brick. I'm not sure where you'd store that on your gun.

Also, like mcguyver stated, you end up using some of the current to operate the regulator.

Yeah. Size is seeming to be an issue. I mean, you can get boost converters that are the size of a dime.. But they are only capable of a few dozen milliamps (or as much as I have seen so far have only been capable of this).

[ILLusion]

NiMH packs are less susceptible to to voltage differences from a fresh "hot" pack and a near dead one compared to Ni-Cad.

Lipo is even more susceptible.

Again, regulators are what's used in the electronics industry to maintain stable voltages, but they do take some power in the process of flipping the transistors.

[kalnaren]

Originally Posted by ujiro

I realized upon saying it, really what I meant was, keep it at the proper voltage when fully charged. Because you can hear a relatively distinct different in the rate of fire and whatnot of a freshly, fully charged battery, and one that has been used for a little bit.

That's an inherent trait of Ni-Mah batteries. Once the battery cools down after charge, you've lost about 10% of it's power (hence why people who fly or race radio controled vehicles always "peak" their batteries). Over the next hour or so it drops by another 10% before sitting at 80%. Ni-Cads are even less efficient. Generally you won't notice too much of a difference under normal loads until the battery actually starts to get low. When I use them in my RC plane (which draws far more power than an airsoft gun), performance drops slightly after takeoff then stays pretty consistent for the next 10 minutes. After that the battery starts to die and performance drops off sharply. After about 12 minutes it will no longer power the plane and the LVC kicks in. Same thing happens in airsoft guns, just a heck of a lot slower.

Originally Posted by ILLusion

NiMH packs are less susceptible to to voltage differences from a fresh "hot" pack and a near dead one compared to Ni-MH.

NiMH and Ni-MH.. isn't that the same thing?

[ujiro]

Alright thanks for the super helpful criticism guys.

I'm gonna do a little more research on this and see what I can find out.

[ILLusion]

Originally Posted by kalnaren

NiMH and Ni-MH.. isn't that the same thing?

Sorry, I just caught that mistake myself. I've corrected it.

[kalnaren]

Originally Posted by ILLusion

Sorry, I just caught that mistake myself. I've corrected it.

No worries.. I figured you meant ni-cad but I wasn't 100% sure, my own battery knowledge is limited.