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Old 10-22-2014, 08:08 AM   #1
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Default HV Lipo Capable Chargers

Hi All,
Can you recommend some balancing lipo chargers (1-6 cell) that have an adjustable high and low voltage cutoff? I'm familiar with the Turnigy Neutrons that have this feature but want to know what my options are. I've done searches but it's time consuming reading through all the hype and specs on every model and some you really can't tell because they may be referring to the different voltage cutoffs for the different type lithiums.
Thanks for your thoughts!

Will
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Old 10-22-2014, 09:57 AM   #2
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iChargers have adjustable termination voltage (at least the models i've used), most likely Powerlabs too. The Turnigy Reaktor should also have the feature as it's based on an iCharger.

EDIT....I just checked the iCharger 306b manual and the highest termination is 4.3v whereas the newer iCharger 4010 Duo will go to 4.35v, so you would need to check specs.
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Old 10-22-2014, 10:55 AM   #3
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Thanks JetPlaneFlyer!
You labeled some of the big hitters here! The ICharger gets pretty expensive but the Reaktor is very reasonable and does have the 306B specs.
Def looking into that one.
Safe landings my friend!
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Old 10-23-2014, 06:22 PM   #4
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Why would you want to seriously overcharge your lipos? I don't understand the benefit. I would expect it to cut at 4.2V per cell.

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Old 10-23-2014, 08:20 PM   #5
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Originally Posted by Suprawill1 View Post
Hi All,
Can you recommend some balancing lipo chargers (1-6 cell) that have an adjustable high and low voltage cutoff? I'm familiar with the Turnigy Neutrons that have this feature but want to know what my options are. I've done searches but it's time consuming reading through all the hype and specs on every model and some you really can't tell because they may be referring to the different voltage cutoffs for the different type lithiums.
Thanks for your thoughts!

Will
I've got two Cellpro Powerlab 8 chargers for my big pile of A123 battery packs. The '8 charger allows a maximum of 4.3 Volts per cell on the LiPo type battery packs. The '8 charger allows a maximum voltage of 3.0 to 4.3 Volts DC for the Lithium type chemistry batteries. That does include the A123's that use the 3.6 Volts DC value.

The Cellpro 6 charger allows a maximum of 6S LiPo batteries. Cellpro also sells an adaptor to allow charging multiple battery packs at once. Each battery is protected by the adaptor with electronic automatic fuse disconnects, just in case something goes whacky.

That said, I also don't know why anyone would want to go over the recommended 4.2 Volts per cell on LiPos. It's likely a point of diminishing returns going over 4.2 Volts, since the battery likely can't store many more milliampere hours, going to 4.3 Volts DC.

Attached is a screen dump on my Cellpro charger. This charger software allows the user to place information on the chargers LCD screen indicating the type and capacity of the battery before connecting the battery to the charger. I even put my name and phone number on the '8 chargers LCD screen that shows up when powering up the charger. The second screen dump shows the Cellpro charger configured to show "My LiPo Batt" on the top LCD line, and 2300 Mah on the bottom LCD line. The charge rate has been assigned as 2.3 Amps, or 2300 Milliamperes.

If you go for the Cellpro charger, or any other charger that can be connected to your computer, be sure to also pick up the USB dongle that allows you to program your charger.


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Old 10-23-2014, 09:27 PM   #6
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Hobbyking has a new line of Lipo's called the Bolt series, they have a new, different chemistry. They are advertized as being high voltage cells. Their proper cutoff voltage is 4.35 volts per cell. Also they are 65C batteries so they should get the job done.

It's only .015 volts per cell differance, but on a 7 cell pack it would give you 1.05 (in theory) more than normal.

One more volt "should" give you about one more KV unit higher prop speed.
It could make a difference in a HV EDF setup.

But it's gonna cost ya !!

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Old 10-23-2014, 10:01 PM   #7
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Originally Posted by AEAJR View Post
Why would you want to seriously overcharge your lipos? I don't understand the benefit. I would expect it to cut at 4.2V per cell.
Both Turnigy and Revolectrix hav come out with new high voltage lipo technology that has a 4.35v cutoff. They could be charged to 4.2 but then you wouldn't get the full benefit of its power. So that being said, it wouldn't be overcharging, it would be charging up to spec.
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Old 10-23-2014, 10:17 PM   #8
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Originally Posted by kyleservicetech View Post
I've got two Cellpro Powerlab 8 chargers for my big pile of A123 battery packs. The '8 charger allows a maximum of 4.3 Volts per cell on the LiPo type battery packs. The '8 charger allows a maximum voltage of 3.0 to 4.3 Volts DC for the Lithium type chemistry batteries. That does include the A123's that use the 3.6 Volts DC value.

The Cellpro 6 charger allows a maximum of 6S LiPo batteries. Cellpro also sells an adaptor to allow charging multiple battery packs at once. Each battery is protected by the adaptor with electronic automatic fuse disconnects, just in case something goes whacky.

That said, I also don't know why anyone would want to go over the recommended 4.2 Volts per cell on LiPos. It's likely a point of diminishing returns going over 4.2 Volts, since the battery likely can't store many more milliampere hours, going to 4.3 Volts DC.

Attached is a screen dump on my Cellpro charger. This charger software allows the user to place information on the chargers LCD screen indicating the type and capacity of the battery before connecting the battery to the charger. I even put my name and phone number on the '8 chargers LCD screen that shows up when powering up the charger. The second screen dump shows the Cellpro charger configured to show "My LiPo Batt" on the top LCD line, and 2300 Mah on the bottom LCD line. The charge rate has been assigned as 2.3 Amps, or 2300 Milliamperes.

If you go for the Cellpro charger, or any other charger that can be connected to your computer, be sure to also pick up the USB dongle that allows you to program your charger.
Thanks for the numbers on the Cellpro! Looks like a great charger. I purchased the Reaktor 300 yesterday which is basically a clone of the ICharger 206B. The Cellpro seems to have more than twice the power as the Reaktor but the Reaktor itself is twice as much as I need for what I charge.
I'm charging the Bolt series 2800mah 65C 4S which has a cutoff of 4.35V. That is why I need and end volt adjustment. 4.3 is the max on most of these end volt adjustables (at least in this price range) and that's fine. That will give me the edge this battery asks for plus a little headroom.
Revolectrix also makes a high voltage lipo that asks for the same cutoff.
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Old 10-23-2014, 10:20 PM   #9
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Originally Posted by Suprawill1 View Post
Both Turnigy and Revolectrix hav come out with new high voltage lipo technology that has a 4.35v cutoff. They could be charged to 4.2 but then you wouldn't get the full benefit of its power. So that being said, it wouldn't be overcharging, it would be charging up to spec.
I did not know that.

Can you provide a link? I looked at the Revolectrix and Hobbyking sites and don't see a listing for high voltage lipos.

Thanks.

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Old 10-23-2014, 10:24 PM   #10
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Originally Posted by Wildflyer View Post
Hobbyking has a new line of Lipo's called the Bolt series, they have a new, different chemistry. They are advertized as being high voltage cells. Their proper cutoff voltage is 4.35 volts per cell. Also they are 65C batteries so they should get the job done.

It's only .015 volts per cell differance, but on a 7 cell pack it would give you 1.05 (in theory) more than normal.

One more volt "should" give you about one more KV unit higher prop speed.
It could make a difference in a HV EDF setup.

But it's gonna cost ya !!
That is correct! Revolectrix also makes a high voltage lipo that asks for the same cutoff numbers. In the Turnigy series, it doesn't seem to cost any more than any above standard lipo and Turnigy also makes several chargers with end voltage adjustment capabilities in competitive price ranges.
The Bolt series is no more than their nano tech series but is not only more powerful, but lighter. Also cheaper than the A spec series.
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Old 10-23-2014, 10:26 PM   #11
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Originally Posted by AEAJR View Post
I did not know that.

Can you provide a link? I looked at the Revolectrix and Hobbyking sites and don't see a listing for high voltage lipos.

Thanks.
No problem. I've been going to school on this technology for the past week. We all learn from each other.

Here's the one I purchased from HK.

http://www.hobbyking.com/HOBBYKING/S...poly_Pack.html


Here's Revo's

http://www.store.revolectrix.com/Pro...0C-SILHV-label
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Old 10-23-2014, 10:34 PM   #12
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Originally Posted by Suprawill1 View Post
Thanks for the numbers on the Cellpro! Looks like a great charger. I purchased the Reaktor 300 yesterday which is basically a clone of the ICharger 206B. The Cellpro seems to have more than twice the power as the Reaktor but the Reaktor itself is twice as much as I need for what I charge.
Yup
I've got the two Cellpro chargers to charge my 12S2P A123 cells. The two chargers are pulling 55 Amps total out of my 12 VDC power supply. (That supply is an alternator connected to a 6 HP gasoline engine.)

That's pretty much what is required when you get to power systems on the order of 3000 watts. That is one of the issues of giant scale models. The costs skyrocket. But they really do fly nice!

For the smaller models, that Cellpro '8 charger is just a lot of overkill in my estimation anyhow.

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Old 10-23-2014, 11:00 PM   #13
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Originally Posted by kyleservicetech View Post
Yup
I've got the two Cellpro chargers to charge my 12S2P A123 cells. The two chargers are pulling 55 Amps total out of my 12 VDC power supply. (That supply is an alternator connected to a 6 HP gasoline engine.)

That's pretty much what is required when you get to power systems on the order of 3000 watts. That is one of the issues of giant scale models. The costs skyrocket. But they really do fly nice!

For the smaller models, that Cellpro '8 charger is just a lot of overkill in my estimation anyhow.
Never flown a giant scale but would love to. Up to this point, I'd always been a gas combustion flyer. Still have 'em but I like this EDF technology. It saved me from the expense of the turbine setup.
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Old 10-23-2014, 11:09 PM   #14
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Originally Posted by Suprawill1 View Post
Never flown a giant scale but would love to. Up to this point, I'd always been a gas combustion flyer. Still have 'em but I like this EDF technology. It saved me from the expense of the turbine setup.
Yeah, electric giant scale models get expensive fast.

I've got two. Cost break down for the Giant Big Stick model is as follows:

Hacker A60-16M motor --------------$240
Castle Creations 80 Amp HV ESC ---$190
24 cell A123 battery pack ----------- $288

That's over $700, and you don't even have the required charging equipment yet. But it sure is nice to just plug in that Hacker A60 motor, go taxi out and go fly, while a club member is spending the afternoon trying to get his 30 cc gasser to start. That's happened more than a few times this summer. Also had a few 30 cc gassers quit in flight, resulting in off field landings, and serious damage to the models involved.

There is no vibration on a giant scale power system, and quality parts such as the Hacker series motors and Castle Creations ESC's will last for many many flights, and many years. Only thing to go bad in a good motor is the bearings, and usually those are replaceable. I've yet to replace bearings in my various Hacker motors. (Except for one where the aileron came off in flight. The crash bent the Hacker A40-10L motor shaft. Both the shaft and bearings were replaced.)

Yeah, you can probably cut that cost in half by going to the cheap China import motors, and using low cost LiPo battery packs. But the components above are high quality, and those A123 cells last, and last, and last, without loss of performance.

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Old 10-24-2014, 01:06 AM   #15
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Originally Posted by kyleservicetech View Post
Yeah, electric giant scale models get expensive fast.

I've got two. Cost break down for the Giant Big Stick model is as follows:

Hacker A60-16M motor --------------$240
Castle Creations 80 Amp HV ESC ---$190
24 cell A123 battery pack ----------- $288

That's over $700, and you don't even have the required charging equipment yet. But it sure is nice to just plug in that Hacker A60 motor, go taxi out and go fly, while a club member is spending the afternoon trying to get his 30 cc gasser to start. That's happened more than a few times this summer. Also had a few 30 cc gassers quit in flight, resulting in off field landings, and serious damage to the models involved.

There is no vibration on a giant scale power system, and quality parts such as the Hacker series motors and Castle Creations ESC's will last for many many flights, and many years. Only thing to go bad in a good motor is the bearings, and usually those are replaceable. I've yet to replace bearings in my various Hacker motors. (Except for one where the aileron came off in flight. The crash bent the Hacker A40-10L motor shaft. Both the shaft and bearings were replaced.)

Yeah, you can probably cut that cost in half by going to the cheap China import motors, and using low cost LiPo battery packs. But the components above are high quality, and those A123 cells last, and last, and last, without loss of performance.
Awesome! If I ever go giant scale, I'll have to look you up for advice.
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Old 10-24-2014, 01:29 AM   #16
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Originally Posted by Wildflyer View Post
Hobbyking has a new line of Lipo's called the Bolt series, they have a new, different chemistry. They are advertized as being high voltage cells. Their proper cutoff voltage is 4.35 volts per cell. Also they are 65C batteries so they should get the job done.

It's only .015 volts per cell differance, but on a 7 cell pack it would give you 1.05 (in theory) more than normal.

One more volt "should" give you about one more KV unit higher prop speed.
It could make a difference in a HV EDF setup.

But it's gonna cost ya !!
Question:

Hobbyking advertises 4.35 Volts per cell for cutoff voltage. BUT, what is the cell voltage at perhaps 20C, as compared to a standard similar sized cell?

If both type cells have the same exact voltage at 20C, methinks going to 4.35 Volts during the charge cycle isn't going to make a difference.

Also wonder about that 65C rating. Might be OK, but flying at 65C for the entire flight, you'll run out of battery power in about 55 seconds.

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Old 10-24-2014, 01:36 AM   #17
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Originally Posted by Suprawill1 View Post
No problem. I've been going to school on this technology for the past week. We all learn from each other.

Here's the one I purchased from HK.

http://www.hobbyking.com/HOBBYKING/S...poly_Pack.html
H'mmm

130 C on a 2.8 Ampere Hour battery is 364 Amps. That is more than double what a starter pulls on your automobile. That is getting close to the the amount of current it takes to melt the #10 wire in that battery pack.

Wonder how many cycles that battery will last at those current levels?

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Old 10-24-2014, 01:38 AM   #18
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Originally Posted by Suprawill1 View Post
Awesome! If I ever go giant scale, I'll have to look you up for advice.
Thanks
I've got just tiny bit of experience in these size electric models.

Harbor Freight Gasoline/Alternator Setup
http://www.wattflyer.com/forums/showthread.php?t=66066,

Great Planes Giant Big Stick Electric Conversion
http://www.wattflyer.com/forums/showthread.php?t=65052

Giant Scale Cessna Model
http://www.wattflyer.com/forums/showthread.php?t=66414

Redwing MXSR Model
http://www.wattflyer.com/forums/showthread.php?t=72225

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Old 10-24-2014, 07:26 AM   #19
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Originally Posted by kyleservicetech View Post
H'mmm

130 C on a 2.8 Ampere Hour battery is 364 Amps. That is more than double what a starter pulls on your automobile. That is getting close to the the amount of current it takes to melt the #10 wire in that battery pack.

Wonder how many cycles that battery will last at those current levels?
Wow, then what am I doing flying jets when I could be hot shotting people's cars for money? lol

130C on the battery I have is the burst rate. 65C is the continuous rate so half that for 182A amps is the draw I'll top out at. In fact, I won't even come close to that on this EDF. The original stock battery it calls for is a 2200mah 20C working with a 45A ESC.
I bought this battery in anticipation of a future upgrade that's going to pull about 60-65A. I will have a 100A ESC for that and will have plenty of headroom on both accounts. Might be a little overkill for now but should fit right in with the upgrade.
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Old 10-24-2014, 07:57 AM   #20
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Originally Posted by kyleservicetech View Post
Thanks
I've got just tiny bit of experience in these size electric models.

Harbor Freight Gasoline/Alternator Setup
http://www.wattflyer.com/forums/showthread.php?t=66066,

Great Planes Giant Big Stick Electric Conversion
http://www.wattflyer.com/forums/showthread.php?t=65052

Giant Scale Cessna Model
http://www.wattflyer.com/forums/showthread.php?t=66414

Redwing MXSR Model
http://www.wattflyer.com/forums/showthread.php?t=72225

Nice looking aircraft, especially the Cessna and MXSR. I would probably gravitate toward something like the Redwing. Looks like a fun flying plane in the vids.
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Old 10-24-2014, 02:17 PM   #21
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Originally Posted by kyleservicetech View Post
Yup
I've got the two Cellpro chargers to charge my 12S2P A123 cells. The two chargers are pulling 55 Amps total out of my 12 VDC power supply. (That supply is an alternator connected to a 6 HP gasoline engine.)

That's pretty much what is required when you get to power systems on the order of 3000 watts. That is one of the issues of giant scale models. The costs skyrocket. But they really do fly nice!

For the smaller models, that Cellpro '8 charger is just a lot of overkill in my estimation anyhow.
Wouldn't it be easier to just leave the car running and run the chargers from the car battery with the car's alternator running? Most car alternators are rated in excess of 120 amps. Even at idle I would bet it could handle 60 amps. That is probably what your AC unit pulls.

I don't know how much fuel you are using in the generator set-up but I would bet the car will use about 1/3 of a gallon an hour which is pretty cheap, easy and quiet.


But that is not really the subject of this discussion. I was just curious as to why you did not use your car to drive the chargers.

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Old 10-24-2014, 07:06 PM   #22
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Originally Posted by AEAJR View Post
Wouldn't it be easier to just leave the car running and run the chargers from the car battery with the car's alternator running? Most car alternators are rated in excess of 120 amps. Even at idle I would bet it could handle 60 amps. That is probably what your AC unit pulls.

I don't know how much fuel you are using in the generator set-up but I would bet the car will use about 1/3 of a gallon an hour which is pretty cheap, easy and quiet.


But that is not really the subject of this discussion. I was just curious as to why you did not use your car to drive the chargers.
Yeah, I've posted a response in a different thread. Don't know if it's reasonable to run a $25K automobile to charge my batteries rather than a $190 setup with my gas engine/alternator setup. Plus, I'm guessing here, but suspect that pulling a constant 55 Amps out of my Caravans alternator, without driving the car for added cooling could fry its alternator. My alternator in my Harbor Freight engine setup runs at about 140F while putting out 55 Amps. You can't hold your hand on it. But most alternators and motors have a pretty high temperature rise specification, so that 140F is reasonable.

Methinks an auto engine will be pulling a lot more than 1/3 GPH at idle. Looking at some farm tractors both gasoline and diesel engine powered, they pull a gallon or more per hour at no load conditions.
http://www.tractordata.com/

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Old 10-25-2014, 12:31 AM   #23
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Depends on the car alternator's rating... but cooling it shouldn't be an issue if the alternator isn't overloaded. I'd expect other stuff to overheat before the alternator if you are not overloading it.

That alternator is built expecting at times to be going across the desert in 100F (or higher) ambient, then the air getting hot cooling the radiator THEN it cools the alternator. They can take a lot of heat.

The amount of gas to run the car vs the custom generator could easily make the generator pay for itself...
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Old 10-25-2014, 02:39 AM   #24
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Originally Posted by fhhuber View Post
The amount of gas to run the car vs the custom generator could easily make the generator pay for itself...
Just wondering.

What are you doing to the automotive engine, if anything, letting it idle for perhaps 5 hours at a time?

I know squad cars do this, but are they specially equipped for it?

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Old 10-25-2014, 03:19 PM   #25
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Originally Posted by kyleservicetech View Post
Just wondering.

What are you doing to the automotive engine, if anything, letting it idle for perhaps 5 hours at a time?

I know squad cars do this, but are they specially equipped for it?
kyleservicetech

You and I and others have discussed this across several thread on different but related topics. The relevance here is whether you can use these high draw chargers off your car, if you want to.

My experience is you can, but that experience does not come from RC it comes from using a 1000 watt power inverter on my car as an emergency power supply. At 1000 watts the inverter is pulling 90 amps from the car.

While I don't run the inverter at 1000 watts all the time there are times when it will surge over 1000 and then maybe drop to about 700 for a stretch. But at 1000 watt it is pulling about 90 amps. I have done that for hours with no ill effect. My 6 cylinder Taurus uses around 1/2 gallon of gas per hour under these circumstances, running constantly.

I loaned the same inverter to my neighbor who used it for a week after Super Storm Sandy. No ill effects on his car either. Probably ran it 8+ hours each day.

Cars are made to be run for extended periods. At 50 amps plus 25 amps to keep the car running you are no where near the peak output of the typical modern day alternator. My Escape alternator is rated for 120 amps. My Taurus is rated for 130. So even if I am pulling 75 amps for an hour I am not pushing the system all that hard.

And if the alternator output, with the car at idle, were not quite enough you pull a small amount from the battery while the airplane charger is at peak and then put it back in as the charger tapers down.

Nothing to load in the car, no external fuel to carry and no generator to buy. And the typical car is quieter than most generators.

If you are thinking of running big battery packs I would say don't rule out using your car as your power source to drive that 12V charger.


LET'S DO SOME MATH


If you have a 8S 5000 mah pack that can be charged at 3C that would be 15 amps (peak) at 33+ volts to the 8s pack. That would be about 500 watts at peak. Of course your charger tapers off as it approaches full charge so you are not pushing 15 amps all the time. You would need to run the car 25 minutes, assuming an empty pack.

That would be about 45 amps from the car side at peak draw. Again the load would taper off as the pack fills up. It takes about 25 amps to run the car with all the accessories and lights turned off. Add 45 for the charger and you are at 70 amps. If you like, add 10 amps to recharge the car's battery while you are running. At 80 amps that would be about 66% of the capacity of my Escape's alternator. Even at idle where it is not putting out its peak I would not expect that to be a problem.

That is well within most auto charging systems and a lot less load than my 1000 watt inverter. Run the car while you charge and you should be fine.

If you are concerned that the car's battery will get run down, leave it running a few minutes after the pack is done and you are putting the pack into the plane to be sure you have topped off the car's battery from the engine start.

To start the car your starter is probably pulling about 250 amps for 10 seconds. That is about 40 amp minutes or about .7 amp hours. Not a lot.

If you are really concerned the car won't start, for about $40 you can pick up one of those jumper packs and just leave it in the car. A lot smaller and lighter than carrying a generator. I actually use one of the jumper packs for charging the 1300 mah motor packs for my e-gliders. Or you can use one of your 3S or 4S airplane packs to jump start the car.
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