Help with several battery questions please

  • Thread starter nduka-san
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In summary, a 12 volt, 75 amp hour battery would be needed to power a small riding lawn mower for 2 hours.
  • #1
nduka-san
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TL;DR Summary
i dont understand batterys that well and would like to know how they work other
i know that batterys are made of a compination of chemicals since i took honors physics but i never really learned how they are made just what theyre made of

2 how large of a battery would be needed for a small tractor with a weight of 300 pounds in this hypotheical scenarior its related to another topic

3 how bad are batterys for the envionment with their chemical cocktails
 
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  • #2
nduka-san said:
Summary:: i don't understand batterys that well and would like to know how they work other

i know that batterys are made of a compination of chemicals since i took honors physics but i never really learned how they are made just what theyre made of

2 how large of a battery would be needed for a small tractor with a weight of 300 pounds in this hypotheical scenarior its related to another topic

3 how bad are batterys for the envionment with their chemical cocktails
Numbers 1 and 3 you hould be able to Google and learn about the different types of batteries. Let's take #2. It's all about how much power you want it to have and how long you want it to operate between charges. A typical small garden tractor weighs about 600 pounds, and has a 25 HP gasoline engine. So let's say your 300 pound tractor would need at least 10 HP. 1 HP = 746 Watts, so you would need an electric motor capable of producing about 7500 Watts, or 7.5 Kilowatts. Now how long do you want it to run between charges? Let's say 4 hours, but you can decide that. Then you need a battery with a capacity of 7.5 * 4 = 30 kWh. How much would that weigh? A Tesla 85 kWh battery weighs 1200 pounds, so a 30 kWh battery will weigh about 400 pounds. Do you see the problem? To run your tractor on a battery, you will either need less power or less time between charges.
 
  • #3
phyzguy said:
A Tesla 85 kWh battery weighs 1200 pounds, so a 30 kWh battery will weigh about 400 pounds. Do you see the problem? To run your tractor on a battery, you will either need less power or less time between charges.
and since it will weight more it will need more time between charges for driving it becuase of the battery weight.

also what about if it was a tractor but it weighed a lot less for example let's say it weighed 200 pounds because rn that's the average estimation for my project also would u have any recemendations for motors? that are ood at saving electricity
 
  • #4
nduka-san said:
also what about if it was a tractor but it weighed a lot less for example let's say it weighed 200 pounds because rn that's the average estimation for my project also would u have any recemendations for motors? that are ood at saving electricity

Will you please write in sentences? You've been asked nicely at least six times.

If a 300 pound tractor needs a 400 pound battery, it is no longer a 300 pound tractor. It's a 700 pound tractor. But that needs a 900 pound battery, so now it's a 1600 pound tractor. Now do you see the problem?
 
  • #5
I do understand ill try to use complete sentences from now on.
I'll have to settle for a small weight on the original build and will have to get a battery with a high power density. Therefore it doesn't weigh too much.
 
  • #6
"and will have to get a battery with a high power density "

How exactly? And do you want power density or energy density? Do your homework.

Let me also suggest that you find out what the Tesla battery costs. Your $1000 budget, if used 100% for batteries, will buy you less energy than @phyzguy showed you needed. You need to address this. An imaginary super-cheap and super-powerful battery is not a solution.
 
  • #7
Vanadium 50 said:
"and will have to get a battery with a high power density "

How exactly? And do you want power density or energy density? Do your homework.

Let me also suggest that you find out what the Tesla battery costs. Your $1000 budget, if used 100% for batteries, will buy you less energy than @phyzguy showed you needed. You need to address this. An imaginary super-cheap and super-powerful battery is not a solution.
i know that tesla batterys are expensive also i meant energy density i was mistaken
 
  • #8
nduka-san said:
I do understand ill try to use complete sentences from now on.

That is a run-on.
That also lasted all of 31 minutes.

You're not being serious, You're on your own now,
 
  • #9
thank you for your previous help.
 
  • #11
Just tracked down the batteries for that Ryobi lawn mower thet @Keith_McClary found.

4 batteries, each 12V, 75AH = 3600Wh total
2 hour run time, 12 hour charge time
Weight 575lbs + rider = about 740lbs total
Battery cost $172 each = USD $688 (Ouch!)

A rough estimate based on battery power and run time yields about 2 to 2.5hp maximum; probably less for 'typical' operation.

Cheers,
Tom
 
  • #12
thank you that's really helpful,but if i reduced the hp would the battery last longer?
 
Last edited:
  • #13
Yes.
 

1. How do I know when my battery needs to be replaced?

There are a few signs that your battery may need to be replaced. These include a decrease in performance or duration, visible damage or corrosion on the battery, and difficulty holding a charge. It is also recommended to replace your battery every 3-5 years as part of regular maintenance.

2. Can I mix different types of batteries in my electronic device?

It is not recommended to mix different types of batteries in your electronic device. Each type of battery has its own unique characteristics and mixing them can cause unequal discharge rates, which can lead to damage to your device or even safety hazards.

3. How should I dispose of old batteries?

It is important to properly dispose of old batteries to avoid harm to the environment. Most cities have designated battery recycling centers where you can drop off your old batteries. You can also check with your local government for specific guidelines on battery disposal.

4. What is the difference between rechargeable and non-rechargeable batteries?

Rechargeable batteries, also known as secondary batteries, can be recharged and used multiple times. Non-rechargeable batteries, also known as primary batteries, can only be used once and must be disposed of after use. Rechargeable batteries are more cost-effective in the long run, but may have a higher upfront cost.

5. How do I properly store my batteries?

Batteries should be stored in a cool, dry place at room temperature. Avoid storing batteries in extreme temperatures as this can affect their performance and lifespan. It is also recommended to store batteries in their original packaging or in a container to prevent them from coming into contact with metal objects.

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