Battery recommendation for Kawasaki 340 engine

Discussion in 'Instruments / Avionics / Electrical System' started by keith103, Jul 26, 2018.

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  1. Aug 9, 2018 #21

    BJC

    BJC

    BJC

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    With weight that close to the limit, would using a cheap lead acid battery as a ground power supply for starting be acceptable?


    BJC
     
  2. Aug 9, 2018 #22

    BBerson

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    A typical 14 volt lithium R/C model battery of about 2 pounds should start the engine. But don't try to charge it from the engine. Instead get a proper R/C lithium balancing charger for $17.
     
  3. Aug 11, 2018 #23

    Armilite

    Armilite

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    ================================================

    I don't know. Is RC Lithium Batteries the same Size and makeup as these Bike, Sled, PWC, etc?

    I see on Youtube a New RC battery is coming out. NCR18650B The Future of RC Batteries?
    https://www.youtube.com/watch?v=adfydRg8PYU
     
  4. Aug 11, 2018 #24

    BBerson

    BBerson

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    R/C batteries are being by used some ultralight electric flyers, but they don't charge them in flight. Should be packed in a metal vented case in case they catch on fire.
    They sell a lawn tractor lithium battery.

    Those green Panasonic batteries are not designed for high cranking loads.
     
    Last edited: Aug 11, 2018
  5. Aug 12, 2018 #25

    Armilite

    Armilite

    Armilite

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    I don't know what's inside my Battery Tender Brand Name 240CCA Lithium, but it's real light weight, I want to say it was 2.4 or 2.6lbs. Those Battery Pack connectors I posted in my thread "Siemens Makes a Big, Light 114hp Motor" look real Simple to makeup different Size Battery Packs.

    Interesting Video. Solderless 18650 Battery System by Vruzend.com
    https://www.youtube.com/watch?v=e_kTMDToieE

    Nice idea! Just about any body could make their own Battery Packs!
    https://vruzend.com/

    Once we know all the Battery Pack Componets Involved and their Weight, we ought to be able to make a Spreadsheet. I'm Electronic Challenged so it needs to be made Simple. We really probably only need 3 Classes of Electric Motors with their respective Battery Packs needed, for say Minimum 1hr of Flight, plus a :20min Reserve, and a plus :10 Battery Reserve account it's my understanding you don't want to totally drain a Lithium. Then make Add-On Battery Packs for more Flight Time, :30, 1:00, 1:30, 2:00, etc. So what Componets are needed to make a 1:30 with these three Motor Sizes. A 30kw is a 20hp to 40hp.

    Ultralight 30kw = 40.2hp

    Small Kitplane 56kw = 75.1hp

    Large Kitplane 75kw = 100.1hp
     

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  6. Aug 12, 2018 #26

    Armilite

    Armilite

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    Like the 30kw = 40.2hp@????rpm. A Chart showing different HP at different Rpm vs Battery Time. With Max Power 40.2hp = 1:30 Time. If you use lower Rpms your Battery Pack will last longer since it's good for 20hp to 40hp.

    Something like this Battery Time at different HP/Rpm's.
     

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  7. Aug 12, 2018 #27

    BBerson

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    My friend said his lithium lawn tractor battery weighed about 2 pounds but was ruined when it got wet.
    He assumed the battery internal electronics got ruined.
     
  8. Aug 12, 2018 #28

    Armilite

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    VRUZEND – Battery building made simple!

    No more spot welding… and no more soldering either!

    Just snap together the VRUZEND bricks and then bolt together your connections. It’s really that simple!

    Lithium battery packs for everything from electric bicycles and skateboards to home energy storage and electric vehicles are crazy-expensive, right?!

    Why is that? It’s because making lithium battery packs used to require special tools and highly skilled workers to use them. But not anymore!

    VRUZEND lithium battery building kits were designed to solve that problem. The plastic end caps slip tightly over the end of the most common lithium battery cell format, the 18650 cell. They can be snapped together like Lego™ bricks to create any size battery.

    Then simply bolt the cells together using the supplied connectors and you’ve got yourself a custom lithium battery pack for a fraction of the price of buying an off-the-shelf lithium battery pack.

    Spot welders are expensive. The good ones cost more than the price of most lithium batteries! Cheap ones are dangerous and prone to breaking when you need them most. Plus, spot welded packs can’t be opened up to replace a single cell if it ever goes bad. VRUZEND kits can!

    With VRUZEND’s innovative DIY battery kits, you simply work with your hands! Snap together the terminal caps, add the connective bars and then tighten the nuts (ok, so you need a socket driver for the nuts, you got us… But it’s mostly tool free!)

    VRUZEND battery kits are designed so that they can be opened up whenever you need if you ever want to expand your battery or replace a cell. Just pull the kit apart and the batteries are easily accessible.

    The plastic end caps work like spring washers or nylock nuts by compressing under the force of the nuts on either end. This provides a counter force to the nut and helps prevent the nuts from loosening even in transportation applications that are prone to vibrations.

    If you’re still worried about vibration loosening of the nuts though, there are other options as well. Loctite or other thread-locking compounds can be added to the nuts, or just a good old fashioned drop of hot glue on the nut will keep it from moving until you’re ready to remove it.

    The VRUZEND battery building kits come with safety post on the ends of every cap to keep your battery terminals and conducting bars lifted off of your work surface while you’re building your battery. This helps prevent accidental short circuits during battery assembly.

    VRUZEND kits can be used to build batteries of nearly any size and shape. You are no longer limited to a small set of battery sizes. You can build the exact battery voltage and amp hour capacity that you need. And if you want extreme capacity, you can build a few battery packs and connect them in parallel, side by side, to create super high capacity batteries that are great for home energy storage.

    The VRUZEND battery building kit really is the best way to build a custom lithium battery from 18650 cells. But don’t take our word for it, try it today!
     

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  9. Aug 12, 2018 #29

    Armilite

    Armilite

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    FAQ: https://vruzend.com/faq/#which-cells

    What is the weight of a pack/how much do the terminal caps weigh?

    Each of the individual caps weighs approximately 4.6 grams, while a nut and bus bar combined weigh approximately 1.25 grams. An entire set of 100 caps, nuts and bus bars weighs approximately 650 grams (1.4 lbs), if you use all of them. The entire kit ends up adding around 1 to 1.5 lbs to a battery, depending on the size battery that you’re building.

    Will the terminal caps melt?

    Polypropylene (the plastic that the VRUZEND terminal caps are made out of) has a melting temperature of 266°F – 320°F (130°C to 160°C). Lithium batteries really shouldn’t be operated in conditions hotter than about 150°F (65°C). If your terminal caps melt, then you likely have bigger problems at the moment.
     
  10. Aug 12, 2018 #30

    Armilite

    Armilite

    Armilite

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    How Big should you make your Battery.
    https://vruzend.com/tech-center/how-big-should-you-make-your-battery/


    # cells in series and Nominal Voltage of Battery Pack.
    1 3.7 V
    2 7.4 V
    3 11.1 V
    4 14.8 V
    5 18.5 V
    6 22.2 V
    7 25.9 V
    8 29.6 V
    9 33.3 V
    10 37.0 V
    11 40.7 V
    12 44.4 V
    13 48.1 V
    14 51.8 V

    The most common configurations are usually 3s, 4s, 7s, 10s, 13s and 14s, as these are the closest configurations to 12V, 24V, 36V and 48V. Remember though that the actual voltage of your battery will be both higher and lower than the nominal voltage during the discharge cycle. To get the full voltage of your battery when fully charged, multiply the fully charged voltage of each cell (4.2 V for li-ion) by the number of cells. So a 10s battery pack is actually 42.0 V when fully charged. The fully drained voltage would be approximately 3.0 V multiplied by the number of cells in series, which would be 30 V for a 10s pack. In actuality, most li-ion cells can be drained down to 2.5 V, but there is very little energy left between 3.0 V and 2.5 V and it is healthier for the cells to stop discharging at 3.0 V.

    Choosing the capacity of your battery
    Next you’ll need to decide on the appropriate capacity of your battery, which is usually measured in amp hours or Ah. The more amp hours in your battery, the longer it will last before running out of charge.

    The capacity of your battery depends on how many cells you have in parallel (remember, you can read up on parallel versus series connections here). Adding more cells in parallel will result in higher capacity. For example, if you use 3.5 Ah cells and have three cells in parallel, you’ll have 10.5 Ah of capacity (3.5 Ah x 3 cells = 10.5 Ah). But if you used 5 cells instead, you’d have 17.5 Ah total.

    In general, the best way to achieve better performance and upgrade your battery is to build a larger capacity battery with a higher Ah value. This is because the more cells you have in parallel, and thus the higher the capacity of the battery, the less load is placed on each individual cell. Think of it like you and your friends carrying a heavy refrigerator. Would rather pick up the refrigerator with three people or five people? It will be much easier to lift with five people, since each person will carry less of the load. It’s the same thing with battery cells! The more cells you have in parallel working together, the larger the capacity and the less load each cell has to support by itself.

    With the VRUZEND kits, each end cap will add a small amount of resistance to your battery due to the spring connector and the bus bars in between them. This adds a little more load to each cell. To use our analogy from earlier, it’s like lifting that fridge while wearing a backpack with a couple books in it. Therefore, you have all the more reason to plan to build a larger capacity battery with a higher Ah value. That way each cell can carry less load and remain happier and healthier.

    The caps in your VRUZEND kit with stainless steel spring contacts are rated for a peak current of 5 A each, and it is better to aim for 3.5 A of continuous current. That means that you’ll want to make sure that you plan to have enough cells in parallel to handle your total current load. A single cell would be able to support a peak of 5 A when using the VRUZEND terminal caps. If you had two cells in parallel, you could support a peak load of 10 A when using the VRUZEND terminal caps. Four cells in parallel could support a 20 A peak load, and so on. So if you know that your load, such as your ebike controller, draws 25 A, you’ll want to make sure you use at least five cells in parallel to give you 25 A of peak current that you can support. More cells in parallel is always better though, as it reduces the load per cell.

    Remember that the current load that your battery can support depends entirely on the number of cells in parallel, and not series. So if you’re building a 36 V battery with 10 cells in series, that doesn’t mean you can support 50 A. You have to calculate your current carrying capacity based on the number of cells in parallel, not series. If that 36 V battery you are building has four cells in parallel and 10 cells in series (making it a 10s4p pack), it can support 20 A when using the VRUZEND terminal caps, since each cap can carry 5 A each.

    In summary…
    In conclusion, the two main factors to consider are your voltage and capacity (measured in amp hours). Your voltage will probably already be decided for you, based on the device you are going to power with your battery. Your capacity is usually up to you, but it is most often best to go bigger than you think. Not only will it give you more run time (and range, if it is for an electric vehicle), but it will keep your cells healthier and lasting longer too as each cell will work less hard.
     
  11. Aug 12, 2018 #31

    Armilite

    Armilite

    Armilite

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    Like this Motor REX50 is designed as a direct drive for small planes with a 1.4-1.5m propeller at 100-120V.

    Due to small dimensions and high torque the motor is used as “Power unit” or “Self-launcher” for gliders.

    The motor has integral hall and temperature sensor and is designed as air cooled for air and mobile applications.

    Maximum Continuous Power for this motor is 20kw(26.8hp) and 25kw(33.5hp) for a short period. Equals what, 2min. 4min, 6min, etc.

    Says Engine Power: 20 - 30 kw = 26.8hp - 40.2hp Max.

    http://www.aeroexpo.online/prod/mgm-compro/product-171210-31062.html
     
  12. Aug 12, 2018 #32

    Armilite

    Armilite

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    ======================================================

    Don't know, I don't wash off my Rider much with a hose, I use my Air Hose to Blow off any Grass usually. They make them Batteries for about anything today.
     
  13. Aug 17, 2018 #33

    keith103

    keith103

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    I will be able to accommodate about 2 to 3 lbs but not the heavier lead acid batteries. Also since the engine I have does not have a manual pull start, having a battery on board is more practical.
     
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  14. Sep 11, 2018 #34

    keith103

    keith103

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  15. Sep 19, 2018 #35

    Armilite

    Armilite

    Armilite

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    A little High for only 270CCA. There are other Brands with higher CCA cheaper on Amazon. But it should work ok. My Battery Tender Brand 240CCA turns over my Yamaha 600 Twin with No problem. Better than any Lead Acid ever did. Cost $98.

    YTZ10S Z10S Lithium Ion Sealed Powersports Battery 12V 300 CCA - Maintenance Free, No Spills, Fully Charged and Activated, Ready to Use (MMG4)
    by MMG
    $109.00
     
  16. Oct 28, 2018 #36

    keith103

    keith103

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    I have used the battery for about 5 hours, and made about may be 25 to 30 starts. It cranks strong, and sustains the charge for at least 6 to 7 starts per use. My engine is still not tuned well, so each start requires keeping starter pressed for quite a few rev's till engine picks up. The battery is only about 6 weeks old, and initially it used to go up to 13.5 volts on re-charge, but now it goes only up up to about 13.25 volts on re-charge, which is what my lead acid 12V battery on my Honda motor cycle delivered in its glory days !
     

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