Hi, having a problem with choosing my battery for our rover project. The problem is we have 4 dc motors with stall current 60A at 24 V and we have 4 of these motors. Should I chose a battery with max 240 amp output meaning the battery that I was planning to chose is nowhere near enough with max 72 amp out (22000 mAh, 35 C, 6S). The problem is previous similar projects never had a battery larger than the one I am about to chose. I want the system to work for at least 30 min (the motors will not be working nonstop so max 6-8 min of all 4 wheels working time). The system has additional low power consumption elements such as cameras small servo motors and wifi moduls as such. Thanks a lot in advance...
the stall current is what the motor will draw if you lock the wheels and the motor tries to still get them to spin ( ie the amperage drawn by a motor when its armature is prevented from rotating)
you'll likely not face that situation, will you?
Sure you could use a 240A battery
However it might be reasonable to make some guesstimates.
Will all four motors stall at the same time or maybe just two, one?
How often will they stall?
Maybe use 4 batteries with 60A max, one for each motor?
Actually, any time the motor shaft is not rotating. All brushed DC motors briefly draw the stall current when starting up. If the power supply can handle that current, the current will drop within a few milliseconds as the shaft gets up to speed, and the windings generate counter EMF.
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thanks - I learnt something
Actually I might face that situation. Since I am planning on desinging a rover that has to overcome inclined surfaces and since rover has a aliminium body I reckon the total rover could be around 40-50 kg. So not sure if anything would stop all 4 wheels at the same time but I was trying to make the calculations on the most unexpected case. What configiration of lipo would you reccomend. I am now considering using 5 lipo's. 4 with very high c ratings and lover capacity and 1 for microcontroller and other components on the rover.
Well I would say not too often. Taking turns and overcoming inclined surfaces will perhaps only drive one or two wheels. We are trying to make a vehicle that is going to perform multiple tasks on a mars like surface.
This web site has calculators and lots of design info to help with just such cases:
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Guys I ve made a terrible mistake by taking 22000 mAh as 2.2 A's causing my 720amp's max current draw to result in 72 
. So thankfull to all of you who cared to answer !!!
Depending on the motor drivers, you will be better off to monitor motor current so that a locked rotor situation cannot occur.
Can you please post links to data/specs of the motors and the drivers you will be using to control them?
Thanks.. Tom.. 
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As I said I reckon the battery I chose has 720 amp max deliverance so the problem is mostly resolved but this is the motor I am planning to use what kind of motor driver would you reccomend if I get a 60A driver could there be a chance that it burns the motors since it is generally advised to use x1.5-x2 amp higher than the max current of the motor
this is one of my options I am considering
I doubt your circuit is drawing anything remotely near that. The wires you are using will instantly vaporize at that current, which is in the range of 4X to 6X what an automobile starter motor typically draws.
For 60A motors, you should be using 8 gauge (AWG) wiring, to each motor.
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Am I making a calculation error here 22.000 mAh 6s li-po with 35 c rating. Correct me if I am mistaken Capacity in A x C rating = Max Amp's ???
I am really a rookie in electronics so I beg your pardon for my questions if they are out of logic
Please post a link to the battery product page.
Be very skeptical of what sellers claim.
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Here is the lipo battery (the site is on my mother tongue but I think the specs are clear)
and here is the motor with stall current 60a
The battery wiring is clearly inadequate to support the claimed 35C current draw for any significant length of time, so don't believe that seller's claim.
The motor draws the stall current for a few milliseconds when starting up, then the current draw drops dramatically as the armature gets up to speed. The 18 AWG motor wiring will limit that starting current to less than 60 Amperes.
The maximum rated current at 24V is 11 Amperes (current draw at maximum rated torque), and you are allowed to draw that only on 25% duty cycle (15 minutes maximum ON time, then 45 minutes OFF).
For steady state operation, the motor current needs to be kept well below 11 Amperes.
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Thank you for your response. I think that really helped me comperhense and avoid some mistakes along the way. 
So new question pops up in my head M I supposed to chose my motor driver considering x1.5 of the stall current or rated torque current that would differ a lot. I don't want to cause any damage to the any of motors since they will be quite expensive for our budget
The driver should be able to handle the rated stall current. Brushed DC motors briefly draw that every time they start moving.
Some drivers allow motor current limiting, for a "soft start", then you can relax the maximum current handling requirement for the driver, as long as the current limit is set properly.
I don't see any mention of current limiting on the product page for the 100A motor driver linked above.
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