Would 8 D batteries be equal to a 12V battery that would run a winch?

Question

we are only allowed to use AA, C, or D batteries for my project and I was wanting to run a winch that uses a 12V battery. Would the winch be able to run very long if I put 8 D batteries in parallel to make 12V

Answer 1

if you are limited to 8 D cells, series them, you my get a minute or two under heavy load. If you are unlimited, series/parallel a bunch of D cells.

Answer 2

A 'D' size battery has a 12,000 mAh or 12 Ah capacity. If you wire the batteries in series you'll have your 12 volts but a winch usually takes a lot of current. The bigger the load on it the more current it will take. Even a small winch such as for an ATV is rated at 0.71 horsepower. This equals about 530 watts and would need 44 amps at full load. Even with no load or a very light load on the winch the D cells probably couldn't produce the current without overheating. If you put enough D cells together, say put 8 in series to get 12 volt pack and made 4 of these packs and put all the pack in parallel you could operate the winch for a total time of about an hour without too much worry of heating the batteries. That would mean 32 batteries but I guess it technically meets the requirements. Better ask and make sure before you go to this trouble and expense. Run the winch in short bursts rather than continuously.

Answer 3

It appears that one of your goals is to use as few (or light) batteries as possible for your project. Using a 12 volt winch with a lifting capacity of a half ton or more is overkill for your application since you really only need about 1/400 HP. Think instead of a small motor which can develop just enough torque to pull a rope for almost the full 2 minutes. A small light duty cordless drill or screwdriver can easily be adapted to run off of as few as 2 or 3 D cell alkaline batteries. AA batteries may be enough for the short time they'll be needed. Make your improvised winch "drum" with a thin shaft that is as long as needed to wind up your rope (fishing line?) in a single layer.



For example, an 1/8" shaft will wind a little less than 1/2" of line per revolution. You would only need about 200 revolutions for 6' of line.



Taking it a step further, a small toy motor that will run on a single cell could be made to work with sufficient external speed reduction through gears or belts and pulleys.



Don

Answer 4

8 D Batteries

Answer 5

not really - I have a 12v motor - low usage that I might be willing to swap for a similar condition 24v

Answer 6

you need to apply some maths, you wish to lift 18kg with a winch of an unspecified power rating.

D cell batteries are about 4 amp, 8 will make 12 v this is 48 watts of available power.

for a crane to lift a 1 tonnie load at 1ms-2 it must exert a force of 10810 newtons (M (a + g)).

Power = work done/ time taken, the units are in joules per sec or watts

if a man lifts a sack of potatoes 50 kg at a constant speed through a distance of 1.5 m in 2 sec, 50 x 9.81(gravity) =490.5 newtons, force x distance = 490.5 x 1.5m = 735.8 joules.

735.8/2 = 367.9 watts.

you may need to use some gearing to compensate for a low powered winch. if 6 steps are 2 metres high, to lift 50 kg 2 metres in 120 seconds requires 4.09 watts per second.

Answer 7

If you're using NiMH 7000 mAH rechargeables, put your cells in series for 12 volts and 7 amps- ampers in series remains the same as one cell. You will get 12 volts and 7 amps, which comes to 56 watts. Since 1 horsepower is 750 watts, that winch will need get less than a 10th horsepower of juice to do its work. Maybe a scooter motor could do light lifting. The winch that you see on a jeep won't get much work done at all- if if even turns- with such a small battery (56 Watts), since they run off a car battery which is much closer to a horsepower in juice.

Answer 8

but then you'd lose the current you needed to turn the winch

Answer 9

Putting 8 D batteries in parallel will yield only 1.5 volts. If you need 12 volts, you must wire them in series.