li Po batteries

iceage

Any Irish retailers selling Li Po batteries and chargers?

Dread-Lock

I saw Li-Po chargers out in Eirsoft the other day...

iceage

naaaa, impossible I just checked uncle T's website and he doesn't list em. http://www.eirsoft.ie/store/index.php?cPath=35&osCsid=dccceb99581c20439ae678b3a69110d9

Shiva

iceage wrote: »

naaaa, impossible I just checked uncle T's website and he doesn't list em. http://www.eirsoft.ie/store/index.php?cPath=35&osCsid=dccceb99581c20439ae678b3a69110d9

LOL....cheap shot.

But justified

iceage

Delighted to hear that there is a new updated website coming Shiva hopefully with stock status. As to Li Po's and chargers I'm sure they'll appear as well.

I know absolutely nothing about these batterys, hopefully there will be advice and possibly a list of what brands of AEG can deal with them i.e. D boys, JG, G+G, etc and more importantly which ones can't!! Also what rate of Batt is suitable for which piece i.e. which Mah is suitable etc.

extremetaz

Not sure of any airsoft retailers selling Li-po's at the moment, but you'll get them, and chargers for them in RC model shops (all models on capel st. etc...)

As for what AEG's will take them, if you install a decent high current voltage regulator with them, then you can use one quite happily at your standard ~9.6V without any fear of additional wear.

You still wind up with a smaller, lighter battery which carries more charge and can deliver more current to the system.

Shiva

iceage wrote: »

Delighted to hear that there is a new updated website coming Shiva hopefully with stock status. As to Li Po's and chargers I'm sure they'll appear as well.

I know absolutely nothing about these batterys, hopefully there will be advice and possibly a list of what brands of AEG can deal with them i.e. D boys, JG, G+G, etc and more importantly which ones can't!! Also what rate of Batt is suitable for which piece i.e. which Mah is suitable etc.

There'll be some info about the batteries, and the chargers required, but nothing about what guns are suitable. Whenever I'm asked about them in the shop, I just say either "no way", or "The manufacturer says it should be ok, but you do it at your own risk".

The thing about it is, other than their smaller size and higher capacity, lipo batteries just output more voltage than their NICD or NIMH counterpart, so theroretically, any gun can use them if they're properly shimmed, have good quality or reinforced gears, decent wiring etc. All they really do is increase the ROF.

Telling people a particular gun is "lipo-ready" leaves us open to all sorts of claims if something goes wrong. Theres a couple of brands and types of gun I can name off-hand that are, according to the manufacturer who made them, and retailers who sell them, "lipo ready", and I know for a fact they've stripped themselves once a lipo was used.

If we tell someone its definitely ok to use a lipo, and it strips, we'll have an irate customer looking for us to fix or replace his gun - so we just dont do it

iceage

Cheers Extremtaz and Shiva, so lets say for discussions sake if you stuck an 8.4v Li Po you should use a Mosfet as well? Just to keep everything under control.

Puding

The problem with the asg is that they only come in 3 cell 11v lipo, a neglected and under used lipo is the 2cell 7.4v, i currenctly running a number of 7.4v 2000mha 15c without issue, there the same power of a large cell 3000mha 8 cell 9v but there the same size as a 8.4v mini, with the added advantage of beacuse there only 2 cells being almost unabel to discharge to a danger level in an aeg.

I would have a look at ebay and a number of of RC shops online they have a large slection for a lot less that the 'airsoft' lipos, which tbh are just rebranded racing packs with a premium added to the price.

Edit: also invest in the best charge/balancer you can buy, don't cut corners

Rogue-Trooper

I picked up a couple of ASG 7.4v li-po's & an ASG charger last week in Eirsoft (and they had a good few more in stock). Got to give them a twirl in my M4 yesterday and have to say am very happy with the result!:)

Puding

I picked up a couple of ASG 7.4v li-po's & an ASG charger last week in Eirsoft (and they had a good few more in stock

thats nice to know, only even seen the 3cells ASGs myself

iceage

Rogue-Trooper wrote: »

I picked up a couple of ASG 7.4v li-po's & an ASG charger last week in Eirsoft (and they had a good few more in stock). Got to give them a twirl in my M4 yesterday and have to say am very happy with the result!:)

Can I ask what make your M4 is?

Rogue-Trooper

iceage wrote: »

Can I ask what make your M4 is?

It's a KWA. Was previously running it on 11.1v li-po's (also ASG) but ROF was TOO good and bordering on ammo-wasting (especially as I favour mid-caps)! Was also very concerned about the damage the 11.1's were doing to the internals (don't want to start ANOTHER rant about KWA's not being 'Li-Po ready'! Back off people!!;)).
I really like the Li-Po's over other types of batteries as they charge quickly, are very consistent, don't seem to suffer from 'memory effect' and don't need to be discharged. They do need to be treated with respect though - I always set the alarm on my phone to remind me to check them when charging as you don't want to overcharge them. Charging usually takes 60-70 mins. It's also worth noting that the 11.1's and the 7.4's require different chargers - they look identical but have different cut-off points. The charging connector is also slightly different so you don't make a mistake!
The batteries and charger cost €25 each in Eirsoft and they had a good few in stock last Friday. Hope this helps.

Masada

what gun are you using it in iceage? pretty much any aeg is "lipo ready", guns often break on regular battrerys and lipo batterys are no exception, if you have a decent setup then you'll be fine.

I ran a G&G MP5 on the 7.4 with no problems, also ran a dboys gearbox on the 11.1 with only mods being 7mm bearings and a shim job.

your effectively only making the gearbox turn faster so you just have to be confident that your gearbox is up to the task, most would take the 7.4 just fine although the wear rate would be higher. but that doesnt mean its going to break tomorrow.

horgan_p

This site really explains the whole lipo thing very very well:

http://infectedairsoft.wordpress.com/tech-info/lithium-polymer-batteries-part-1/

Puding

he same guy also has a great thread over on arnies on everything to do with lipo, well worth a read

http://www.arniesairsoft.co.uk/forums/index.php?showtopic=150394&st=0&start=0

iceage

Masada wrote: »

what gun are you using it in iceage? pretty much any aeg is "lipo ready", guns often break on regular battrerys and lipo batterys are no exception, if you have a decent setup then you'll be fine.

I ran a G&G MP5 on the 7.4 with no problems, also ran a dboys gearbox on the 11.1 with only mods being 7mm bearings and a shim job.

your effectively only making the gearbox turn faster so you just have to be confident that your gearbox is up to the task, most would take the 7.4 just fine although the wear rate would be higher. but that doesnt mean its going to break tomorrow.

The ones we have is a D boys M4 a1, JG G36c, and a DE UMP. all using small type firefox 8.4 v batts 1500 Mah, a 8.4v stick in the UMP also the same in a Galaxy mp5k.

Also the mention of a regulator? I take it this is a Mosfet switch? and is it advised that thet should be used in conjuction with Li Po batteries. Sorry for all the questions guys but this seems to be the next step in Battery technolgy for Airsoft and I'm kind of interested. Will check out the earlier links mentioned later this evening. Thanks guys for all the info.:)

hoplite

I have started to use 7.4V Lipo in some of my AEGs and so far so good very pleased.

theburi

hoplite wrote: »

I have started to use 7.4V Lipo in some of my AEGs and so far so good very pleased.

If you don't mind. Where did you get Li-po's and what kind of Charger/balancer do you use?

Thanks

peter-pantslez

hoplite wrote: »

I have started to use 7.4V Lipo in some of my AEGs and so far so good very pleased.

what kind of performance increase do you get by using a 7.4v lipo vs a 8.4 normal battery?

hoplite

theburi wrote: »

If you don't mind. Where did you get Li-po's and what kind of Charger/balancer do you use?

Thanks

Yep I got the charger and batteries from Ehobby

Charger does 7.4v and 11.1v Lipo as well as NiMH and NiCD
http://shop.ehobbyasia.com/bb-battery/batteries/chargers-dischargers/imax-b6-balance-charger.html

I got two of these
http://shop.ehobbyasia.com/bb-battery/batteries/lithium-batteries/hot-power-7-4v-2200mah-15c-lithium-battery.html

And two of these
http://shop.ehobbyasia.com/bb-battery/batteries/lithium-batteries/hot-power-7-4v-1600mah-12c-lithium-battery-ak-stick.html

hoplite

peter-pantslez wrote: »

what kind of performance increase do you get by using a 7.4v lipo vs a 8.4 normal battery?

I would say the performance of 7.4V lipo is on a par with 9.6v NiMh if anything slightly better in terms of ROF.

Previous posters comments on speed of charge and lack of memory effects are true for me as well so far.

I think its important to note that you have to consider safety when using lipo. I charge my batteries on a tiled floor in my conservatory in a clay flower pot.

Extract from

http://www.rcgroups.com/forums/showthread.php?t=209187

After seeing the many many posts on LiPoly's and answering similar questions time after time I've decided to put up a guide for using LiPoly batteries.

Lithium batteries are the preferred power sources for most electric modelers today. They offer high discharge rates and a high energy storage/weight ratio. However, using them properly and charging them correctly is no trivial task. There are many things to consider before using lithium cells for e-flight. But none is more important than safety.

1. Charging/Saftey IMPORTANT!
Until you are willing to follow all saftey precautions, DO NOT use lithium batteries. If your a type of person that prefers to push the limits of products, or be haphazard about following saftey requirements. Lithium technology is not for you. Read on to find out why.

Lithium cells must be charged very differently than NiCad or NiMH. They require a special charger specifically designed to charge lithium cells. In general any charger that can charge lithium ion can charge lithium polymer, assuming that the cell count is correct. You must NEVER charge lithium cells with a NiCad or NiMH only battery charger. This is dangerous. Charging cells is the most hazardous part of using lithium batteries. EXTREME care must be taken when charging them. It is important to set your charger to the correct voltage or cell count. Failure to do this can cause the battery to spew violent flames. There have been many fires directly caused by lithium batteries. PLEASE BE RESPONSIBLE when charging lithium batteries.

Here are a few MANDATORY guidelines for charging/using LiPos (Lithium Polymer Batteries).


1. Use only a charger approved for lithium batteries. The charger may be designed for Li-Ion or Li-Poly. Both batteries are charged in exactly the same. Some older cell phone chargers may charge the batteries .1 volt to low (4.1 vs 4.2), but that will not harm the battery. However, inexpensive lithium chargers are widely available and the use of cellphone chargers is highly discouraged.
2. Make certain that the correct cell count is set on your charger. Watch the charger very closely for the first few minutes to ensure that the correct cell count continues to be displayed. If you don't know how to do that, get a charger that you do know how or don't charge the batteries.
3. Use the Taps. Before you charge a new Lithium pack, check the voltage of each cell individually. Then do this after every tenth cycle there after. This is absolutely critical in that an unbalanced pack can explode while charging even if the correct cell count is chosen. If the cells are not within 0.1 volts of each other then charge each cell individually to 4.2 volts so that they are all equal. If after every discharge the pack is unbalanced you have a faulty cell and that pack must be replaced.
Taps are provided on most new lithium packs. Taps give you the ability to check individual cell voltages and charge one cell at a time. Make sure and get the appropriate connector to go into your taps. Don't try to stick you volt meter probes in the taps to measure voltage. They could slip and short your cells. Don't try to charge more than one cell at a time from the taps. Unless you have an isolated ground charging system, you'll short your batteries out. Refer to your individual cell maker for tap pin-outs.
4. NEVER charge the batteries unattended. This is the number one reason for houses and cars being burned to a crisp by lithium fires.
5. Use a safe surface to charge your batteries on so that if they burst into flame no damage will occur. Vented fire safes, pyrex dishes with sand in the bottom, fireplaces, plant pots, are all good options.
6. DO NOT CHARGE AT MORE THAN 1C unless specifically authorized by the pack vendor. I have personally had a fire in my home because of violating this rule. Todays highest discharge batteries can supposedly be safely charged at greater than 1C, however so far in all cases doing so shortens the life of the pack. Better to buy 3 packs than to try to charge 1 pack 3 times quickly. This may change in the future but as of Winter 2005 1C is still the recommended charge rate.
7. DO NOT puncture the cell, ever. If a cell balloons quickly place it in a fire safe place, especially if you were charging it when it ballooned. After you have let the cell sit in the fire safe place for at least 2 hours. Discharge the cell/pack slowly. This can be done by wiring a flashlight bulb of appropriate voltage (higher is voltage is ok, lower voltage is no) up to your batteries connector type and attaching the bulb to the battery. Wait until the light is completely off, then throw the battery away.
8. If you crash with your lithium cells they may be damaged such that they are shorted inside. The cells may look just fine. If you crash in ANY way carefully remove the battery pack from the aircraft and watch it carefully for at least the next 20 min. Several fires have been caused by damaged cells being thrown in the car and then the cells catch fire later and destroys the car completely.
9. Charge your batteries in a open ventilated area. If a battery does rupture or explode hazardous fumes and material will spew from the battery.
10. Keep a bucket of sand nearby when you are flying or charging batteries. This is a cost effective way to extinguish fires. This is very cheap and absolutly necessary.
11. It can happen to you, do not think to yourself that “it won't happen to me” as soon as you do that it you'll be trying to rescue your kids from your burning house or car. I'm very serious about this.

extremetaz

@paul: that's a decent link, puts things out there in nice simple terms

hoplite wrote: »

I would say the performance of 7.4V lipo is on a par with 9.6v NiMh if anything slightly better in terms of ROF.

this is probably true alright, reason being that the lipo can deliver more power than the NiMh even at the lower voltage on account of its lower internal resistance. Futhermore, the voltage of the Lipo wont drop off by anywhere near as much as the NiMh when current is being drawn from it.


it's important to note people that lipo's are only available in increments of 3.7V.

7.4V is a 2 cell battery.
11.1V is a 3 cell battery.
there is nothing in between these increments.


@Iceage: a MOSFET ain't the same thing as a Voltage reg, although "technically" is "can" perform the same job, it's not designed to do it and implimenting it in such a manner would be, at best, finnicky.

If you want to Lipo your AEG wit the least possible amount of fuss then the best bet is to try out the 7.4V as Hoplite has suggested.

I'm planning on running an 11.1V through a variable voltage reg initially - means I can dial in whatever voltage I want in order to optimise the setup. (so, nice and safe initially, and pressing the envelope later on ).

iceage

Thanks Extremetaz. A 7.2v Li Po sounds like the place to start.

hoplite

Yep I think 7.4V is a good place to start and to be honest is powerful enough for my needs.

If I put an 11.1V into a stock AEG I'd be expecting strpped gears or shredded pistons.

Thats not to say 7.4V wont do that either but the risk is reduced.

edit

I'll benchmark ROF numbers on 8.4V NiMH 9.6V Nimh and 7.4V LiPo when I get a chance.

Gatling

has anybody got a rough list of what will take li-po and what wont ,
thinking of trying lipo with a jg 416 then a tm when upgrades are done,
is there anything other than shims and bushings that is recommended upgrading first heard anding low resisitant wiring can help

extremetaz

Gatling wrote: »

has anybody got a rough list of what will take li-po and what wont ,
thinking of trying lipo with a jg 416 then a tm when upgrades are done,
is there anything other than shims and bushings that is recommended upgrading first heard anding low resisitant wiring can help

I don't think there are many that people will confidently say can take a lipo from stock.

Again - hoplite's 7.4V suggestion should prove fine but dumping an 11.1V straight in mightn't be wise.

My main concern regarding the 11.1V again mimics hoplites - the rpm boost that much extra power can provide may well lead to the spur gear rotating back to catching point before the piston has seated. The consequence of the two gear sets meeting in motion is almost certainly gonna be stripped teeth and all the nastyness that comes with it.

Low resistance wire will do two things:
- reduce heating in the wire when current is flowing
- reduce the power lost due to heating in the wire

Hence honestly - unless you're already at the stage of tweaking for max performance, it's no big concern.

However, depending on the guage of wire in your AEG, there is merit to considering installing higher current rated wire without going to the additional cost of low resistance stuff.

hoplite

@extremetaz

Its fair to say your technical knowledge and tuning ability far exceed my own

Thats why I'll be sticking with 7.4v Lipo for now and hoping nothing breaks

One of the main reasons I went down the lipo route is that I found it hard to find a decent stick battery for my AK47 and MP5k.

Problem now solved.

extremetaz

hoplite wrote: »

One of the main reasons I went down the lipo route is that I found it hard to find a decent stick battery for my AK47 and MP5k.

to be honest, that's exactly why I'm switching - twice the charge from the same size package means no more dead batteries on game day.

+ no memory effect and reliable charging!

peter-pantslez

lads just found these on ebay and thought you might find them interesting

http://cgi.ebay.ie/2X-Fireproof-Lipo-Li-Po-Battery-Safety-Guard-Charge-Bag_W0QQitemZ150334747719QQcmdZViewItemQQptZUK_ToysGames_RadioControlled_JN?hash=item150334747719&_trksid=p3286.c0.m14&_trkparms=72%3A1301%7C66%3A2%7C65%3A12%7C39%3A1%7C240%3A1308

Stercus Accidit

I heard that if used too much, ie, used until the voltage drops to a certain point, they also go on fire.

Is there a way to avoid this? Integrating an electronic device of some type, or do you just have to guess when they are near empty?

Thanks.

Dread-Lock

Stercus Accidit wrote: »

I heard that if used too much, ie, used until the voltage drops to a certain point, they also go on fire.

Is there a way to avoid this? Integrating an electronic device of some type, or do you just have to guess when they are near empty?

Thanks.

You should read:
http://infectedairsoft.wordpress.com/tech-info/lithium-polymer-batteries-part-1/

It will answer all your questions.

extremetaz

Stercus Accidit wrote: »

I heard that if used too much, ie, used until the voltage drops to a certain point, they also go on fire.

Is there a way to avoid this? Integrating an electronic device of some type, or do you just have to guess when they are near empty?

working from the second paragraph back.

"is there a way to avoid this?"
- taking the instance whereby you mean is there a way to avoid discharging a lipo battery beyond rated capacities - then yes, it can be done, however, if the motivation for doing so is on account of the "fire hazard" myth then there's simply no need. Bottom line, if it doesn't have enough power to turn a motor, it definitely doesn't have enough power to start a fire.

as for guessing when they're near empty - if you do intend to employ some form of charge monitoring then that's essentially what you'll be doing yes. I've yet to research this point fully but if you'll permit educated speculation, the charge tolerences for a lipo battery are between +0.05V at full charge and -0.05V at rated dishcharge - hence in the instance of a 7.4V cell, the max discharge condition should be satisfied at approximately 7.35V. The requisite loading for this value to apply however, I've no idea of at the moment.

working back up to the first paragraph; if they're in a state of discharge, they aren't going to go on fire - end of!

Beast ASI

All guns will take 7.4 lipo's - they're roughly the same as a 9.6 nimh.

Most guns will take 11.1 lipo's if setup right.

peter-pantslez

lads does anyone know of any stocks that will house a 7.4v lippo??

besides a full stock..

Stercus Accidit

An individual cell is 3.2 v yes?

Apparently, the battery once below 3.1 becomes damaged, and can't hold a full charge again.

If I'm playing a game, and my gun stops firing, that cell would have to be pretty tapped out, and I could have gone too far.


My question is is there a reliable way to tell when you should stop using the battery, and recharge before damaging it, bar wiring a multimete into my aeg!
I know there are indicators that can be wired in, but there is no major rof drop or inability to turn the motor before this critical damage point is there?

extremetaz

Individual cells are 3.7V.

Not sure about the max discharge condition - I'd be inclined to say though that given the power required to drive a motor, you'll be nowhere near critically discharged before the motor stops turning.

Stercus Accidit wrote: »

An individual cell is 3.2 v yes?

Apparently, the battery once below 3.1 becomes damaged, and can't hold a full charge again.

Stercus Accidit

Is that the case then, that once the proper precautions are taken for charging, the cell can be ran until it won't turn the motor any more?

mobprop667

i use an 11.1 li po in my g&g gr300s with no problems. have been for 3 months now. huge rate of fire and so far no problems.

Head_Hunter

Stercus Accidit wrote: »

My question is is there a reliable way to tell when you should stop using the battery, and recharge before damaging it, bar wiring a multimete into my aeg!

You need one of these to check the voltage on the lipo battery cells, I use them all the time. Don't let any cell get below 3v, personally I don't allow a cell to fall below 3.2v.

Stercus Accidit

The only question I really have I suppose, is can an aeg deplete a lipo to the point it can become damaged?

I use my batteries until they fail to turn the motor, then swap out (rarely happens bar big games) but I do want to move on to li-po.


I'll pick up one of those balancers if I have to, but I'll freely admit, I'm not li-po savvy, and find most guides are based around models motors, with a lower load than an airsoft which has a minimum voltage required to compress the spring, possibly before the damage point in a li-po.

http://www.rcqatar.com/batteries-and-chargers/lipos-command-respect-!/?action=printpage

Going by this article and my interpretation, a li-po would easily over deplete itself in an aeg, but its not deffinitely covered.

peter-pantslez

extremetaz wrote: »

I don't think there are many that people will confidently say can take a lipo from stock.

Again - hoplite's 7.4V suggestion should prove fine but dumping an 11.1V straight in mightn't be wise.

My main concern regarding the 11.1V again mimics hoplites - the rpm boost that much extra power can provide may well lead to the spur gear rotating back to catching point before the piston has seated. The consequence of the two gear sets meeting in motion is almost certainly gonna be stripped teeth and all the nastyness that comes with it.

Low resistance wire will do two things:
- reduce heating in the wire when current is flowing
- reduce the power lost due to heating in the wire

Hence honestly - unless you're already at the stage of tweaking for max performance, it's no big concern.

However, depending on the guage of wire in your AEG, there is merit to considering installing higher current rated wire without going to the additional cost of low resistance stuff.

what current rating would you recommend? and where can i get low resistance wiring?

thanks

Stercus Accidit

Any rc shop would stock it I imagine, and you can get low res connectors such as deans or mini deans on ebay.

Mosfets, you can get an ordinary one installed, richie in eirsoft does mosfets, or you can get a more complex active braking mosfet with auto reset fuses online from extreme-fire.com.

peter-pantslez

thanks,

but do you know whats the best current rating to get the cable for?

Stercus Accidit

I think its high current 12 guage wire you want, my mosfets linked in with 12g wire, with 20g for low current wiring to the trigger itself. Unsure of amp ratings though.

Alzir

1.5mm square or 18 AWG (american wire gauge) is good for about 16 or 18A I think. That should be good enough for a standard AEG ciruit. Any electrician on here would have a beter knowledge. All good elctrical supplies will have reels of cable. Get panel flex its not as ridgid and easier to work with.

Beast ASI

I use 16AWG on any new wiring installs - Not much point going thicker than that though and 18AWG if 16 won't fit - Both do the trick

extremetaz

@stercus: yup - it's pretty safe to say that you can run the batteries until the motor won't turn without any fear of damage. Reason being, it takes far more power than the battery will have at the point of rated discharge to turn the loaded motor. Only way you'll run the battery beyond critical discharge is if you continue to hold the trigger pulled even when the motor won't turn.

12 AWG is f*ckin' huge stuff - I wouldn't bother with it personally as although you can be drawing up to 20A, it's never for very long so you don't need wire thats rated to handle that sort of current consistently.

@beast & alzir: Spot on, either of those would have been my recommendation as well.

@peter: not really worth your while bothering with low-res wire. It's really only used where there's a consistently high power flow in temperature critical or space constrained areas, or for audio system wiring where non-uniform impedance can cause problems. No idea where you'll get it.

Tactical

Alzir wrote: »

1.5mm square or 18 AWG (american wire gauge) is good for about 16 or 18A I think. That should be good enough for a standard AEG ciruit. Any electrician on here would have a beter knowledge. All good elctrical supplies will have reels of cable. Get panel flex its not as ridgid and easier to work with.

1.5sq is only good for 13 Amps. 2.5sq is good up to 20 Amps.

1.5sq typically used in a domestic application for lighting circuits that you'll never find fused at more than 10 Amps at the distribution board.

extremetaz

Tactical wrote: »

1.5sq is only good for 13 Amps. 2.5sq is good up to 20 Amps.

1.5sq typically used in a domestic application for lighting circuits that you'll never find fused at more than 10 Amps at the distribution board.

Yeah, but you cant really apply building reg logic to this instance as the load is only momentary. if the load were constant then you'd be exactly right.

For instance - the motor in the average AEG, assuming 9.6V @ say 13A would equate to almost a 125W motor, which is kinda impossible in the package it's contained in. It's most likely rated for (at most) in the region of about 30W, however, it (just like the 18AWG) can handle far higher than rated nominal current levels for short bursts.

It all comes down to heat generated - under constant load, you'll generate a lot of heat in smaller wire. However, in short bursts, the heat has plenty of time to dissipate so there's no problem.

Tactical

But remember the I2R losses.

The smaller the cable used, the larger the voltage drop will be.

Ok, the run is relatively short and using the heaviest cable practical will see as little voltage drop as possible.

I'd still worry about sustained firing and the current draw.

Consider using a cable of cross sectional area no less than that connected to the battery at the very least.