birel19

Should I get a Intellect 1400 6 cell, Intellect 1400 7 cell, 6cell Elite 1500, or 7 cell elite 1500 for my rc18t?
Which will have longer runtimes, more speed, and which is better for brushless?
I want to go brushless but for now I am doing the upgrades necessary for my truck to handle the power[8D] I just ordered all arounf factory dogbones, motor mount, steel turnbuckles, and derilin sedan wheel adapters. In the future I want to use the Trinity 5800kv cobalt motor

Mattdg67

The 7 cell elite 1500 would be the best unless you want to get a Lipo. I would also suggest the C4 9400kv brushless motor.

i8tweety

My Feedback: (11)

The longest run-time would be from the 6 cell 1500 mAh pack. The 7 cell pack would give you better acceleration and top end, but less run-time.

birel19

How much less runtime with the elite 1500 7 cell?

Haulin Azz

not much a few minutes probably

phaythe

What is the difference? 1.2 volts!

A 7 cell pack adds extra weight but provides more voltage, so the motor spins up faster. Runtime shouldn't be affected much at all. Definitely a better choice if you're wanting to run brushless, but at that point I would suggest running 2 or 3 cell Li-Po packs instead. Those packs will get you the most power out of a brushless setup, especially a 3-cell. You'll watch the motor come alive.

birel19

If I can afford it I am going to get a 7 cell elite 1500 pack, if I cant I will purchase a 7 cell intellect 1400 pack. Then I will purchase the brushless system!!

i8tweety

My Feedback: (11)

Going from a 6 cell (7.2 volt) to a 7 cell (8.4 volt) will result in a runtime reduction of approximately 14%. That is, if a 6 cell, 1500 maH pack runs for 10 minutes, a 7 cell, 1500 maH pack would run for a little over 8 and a half minutes.

Racing T

really? why is that if both batteries are the same mah just that one have a extra cell?

joeyblaze

x2................

Seek and Destroy

I would get the ib's. THe elite bats like to vent or sweel up, so I've heard. But they are great cells.

Dokioto

Could you explain more? I would think (I don't know it all) that the 7-cell would have more run time...

TheArsonist21

Get the most cells you can fit.

I crammed an 8-Cell into my Mini-LST and its just insane!

-Inverted-

Nope, all you are doing is adding an extra 1.2 volts.

Racing T

but why less run time because of more cells?

Silentbob343

When you wire batts in series you combine thier voltage, but they share the same capacity, i.e. 7 cells=8.4 volts with 1400mAh. Compared to the 6 cell you are getting 7.2volts with 1400mAh. More volts will drain the battery faster hence why the 7 cell will have reduced run times.

Now if you were to wire the batts in parallel then you combine thier capacity, i.e. 7*1400=980mAh, but the total voltage would be 1.2.

timmygreek

I hate to say this but capacity is capacity. It does not change the current drain in a 6 or 7 cell pack wired in series. The motor determines the current drain.

carmatic1

yes, and the motor will drain the battery faster if it obeys ohm's law : current = voltage over resistance ... this resistance is how 'the motor determines the current drain' , as you put it...

Dokioto

Thats what I was trying to figure out... It didn't make sense to me.

Silentbob343

I simplified a bit too much, but carmatic was kind enough to to clear it up.

Racing T

ooh ok now I understand...

jaymac

I have the intellect 7 cell with AON4900 in my RC18T and it has a heap of torque even with the MT gearing (although I have never had any other battery so I cant compare) but its a heap of fun!

i8tweety

My Feedback: (11)

Heat plays a role in the reduced run-time, but it's not the main contributor. Heat will increase the internal resistance of the motor. The biggest factor is the higher amp draw. Here's how it works.

1500 mAH batteries can sustain 1.5 amp discharge rate for 1 hour on a full charge (1 cell or 100, doesn't matter)

If you remember electricity class (oh too familiar for me)

Voltage = Current * Resistance

Current = Voltage / Resistance

If we hold resistance constant (as pointed out earlier, it will actually go up slightly due to heat)

Current = Voltage / Constant

for a 6 cell pack (7.2 Volts)

Current = 7.2 V / Constant

For a 7 cell pack (8.4 Volts)

Current =8.4 V/Constant

The addition of 1 cells (1.2 Volts) results in an increase of current by 17% (1.2V/7.2V) or a reduction of run-time of 14%.




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