The costs of running this huge site are paid for by ads. Please consider registering and becoming a Supporting Member for an ad-free experience. Thanks, ECF team.

Battery DIY Models & Other Useful Information

Discussion in 'Battery Mods' started by M & M, Feb 24, 2010.

Tags:
Thread Status:
Not open for further replies.
Image has been removed.
URL has been removed.
Email address has been removed.
Media has been removed.
  1. Bole

    Bole Full Member

    Jul 17, 2012
    Finland
    Usefull thread!
     
  2. Koman

    Koman Moved On ECF Veteran

    Jan 7, 2010
    lv
  3. ar_zaem

    ar_zaem Full Member Verified Member

    Mar 10, 2013
    Kuala Lumpur
    im started to luvin this thread. might as well mod my cig.l.
     
  4. DrBeaker

    DrBeaker Registered Supplier ECF Veteran

    Jul 24, 2013
    Lab City USA
  5. DruidPriest

    DruidPriest Senior Member ECF Veteran

    Sep 30, 2013
     
  6. ian-field

    ian-field Super Member ECF Veteran

    Dec 3, 2013
    Hertfordshire
    In the UK, we have little hacking groups springing up all over the place - small groups of people who enjoy taking things apart and adapting them for other uses.

    Such a group might well enthusiastically wade into turning a flashlight into an e-cig.
     
  7. Doug_xx2

    Doug_xx2 Senior Member ECF Veteran

    Dec 30, 2013
    Penn Yan, ny
    are all 18650 batteries high drain? do they all have the same c rating? I am getting a dna 30 board and one of evolvs usb chargers would that work to recharge an 18650? would an 18650 be an appropriate long lasting battery to power a dna 30 pumping 30 watts through a 1.5 ohm dripper with dual coils?
     
  8. ian-field

    ian-field Super Member ECF Veteran

    Dec 3, 2013
    Hertfordshire
    The laptop battery pack I stripped only contained 18350, but one of those lasts me all day. The shunt regulator charger I built gets pretty much the full 500mA from a USB wall-ward when the battery is fully discharged, this just about fully charges it in 24h.

    For original equipment batteries (about 200mAh) you can get away with a TL431 shunt regulator - it can only handle 100mA so that is the most the dropping resistor should supply at a terminal voltage of 4.2V, at that point the TL431 is bypassing all the current.

    I'll leave it as an exercise for the student how to get more than 100mA shunt current.
     
  9. Doug_xx2

    Doug_xx2 Senior Member ECF Veteran

    Dec 30, 2013
    Penn Yan, ny
    I think that the evolv usb charging board doe 500 mah but I might be wrong

    I ended up getting 2 Sony US18650VTC4 2100mAh Li-Ion Rechargeable High Drain Battery 30A. I was hoping to get a flat cell but couldn't decide which one to get. maybe I will strip it down later and change the battery if I find a good one.
     
  10. ian-field

    ian-field Super Member ECF Veteran

    Dec 3, 2013
    Hertfordshire
    USB chargers conforming to the 500mA spec are cheap and readily available, but you can sometimes find regulated 5V wall-warts from routers that are capable of in the region of 1.2A.

    It would be unwise to try mating this up to the end of charge chip from an original e-cig battery unit - it could fail short circuit and fry the battery.

    Currently I'm using a shunt regulator with a standard spec USB wall-wart, it does what I need so I've no immediate plans to modify it further - but it would be easy to upgrade for faster charging.
     
  11. Doug_xx2

    Doug_xx2 Senior Member ECF Veteran

    Dec 30, 2013
    Penn Yan, ny

    This is what the datasheet for the dna 30 says I cannot find a datasheet for the usb charging board. Does that sound like it would work?


    Battery:
    A single cell rechargeable lithium chemistry battery is recommended. Either a lithium ion or a
    lithium polymer type can be used. Any battery used should be rated for a MINIMUM of 12 amps
    continuous discharge current. High C rated lithium polymer or IMR cylindrical cells are strongly
    preferred. Make sure that all contacts and connections are capable of handling at least 12 amps.
    Charger:

    Evolv offers an accessory DNA Charger which is USB powered and provides a 500 milliamp
    charge current. The use on an onboard charger is optional – a removable battery will also work.



    This is what the shop says about their charging board


    DNA Charger
    Our Micro-USB charging module lets you add the functionality of onboard charging to your DNA 12 and DNA20D projects or can be used as a standalone charger for non-DNA projects. It is designed for charging 3.7V 1S Li-Ion and Li-Poly cells. An onboard status LED illuminates red when charging, green when fully charged, and orange when no battery is present. Mounting holes for #2 screws are provided for easy attachment.

    Add To Cart
    $7.50

    Input Voltage: 4.5-5.5VDC

    Charge Current:

    500mA
    Charge Voltage:

    4.2V
    Input Interface:

    Micro-USB
    Dimensions:

    0.5" x 0.6" x 0.14"
    Mounting:

    #2 screws 0.30" apart on center
    Purpose:

    charger for 3.7V 1S Li-Ion & Li-Poly Cells (can be used with the DNA 12 or as a standalone charger)



    I'm not sure I will have to do further research.....
     
  12. ian-field

    ian-field Super Member ECF Veteran

    Dec 3, 2013
    Hertfordshire
    The Vapourlites charger is little more than a 15R current limiting resistor - the important bit is the end of charge disconnect chip in the battery unit.

    In my earlier experiments I tried reducing the resistance to increase the current, but the disconnect chip got noticeably warm - it just wasn't worth the risk of the chip failing S/C and flaming the battery, so I developed a shunt regulator that bypasses 100% of the charge current when the battery is full.
     
  13. Doug_xx2

    Doug_xx2 Senior Member ECF Veteran

    Dec 30, 2013
    Penn Yan, ny
    these are the specs for the battery but perhaps I should look into a safety backup...
    or maybe design for removal and charging in wall unit

    Maximum Continuous Discharging Current: 15A
    Maximum Rated Discharging Current: 30A
    Maximum Pulse Discharging Current: 60A
    Maximum Continuous Charging Current: 6.5A
    Nominal Voltage: 3.8V
    Maximum Charge Voltage: 4.2V
     
  14. ian-field

    ian-field Super Member ECF Veteran

    Dec 3, 2013
    Hertfordshire
    All you really need is a shunt regulator set so it bypasses 100% of the charge current at exactly the maximum charge voltage.

    With a simple current limiting resistor, the charge current at minimum cell voltage will only be a little bit more than the maximum current the shunt regulator can bypass.

    You could also sense cell temperature and use a comparator to operate an emergency shutdown relay - but I think the safe/jet of flame margin is quite narrow.
     
  15. Doug_xx2

    Doug_xx2 Senior Member ECF Veteran

    Dec 30, 2013
    Penn Yan, ny
    well I will admit you are talking over my head but I love to learn and I just bought some stuff because I decided I want to learn electronics sooo.... google read try is the next course of action for me :) thanks for the idea!!!

    BTW this is my very first mod I built it last night in a few hours. I was bored+Broken flashlight+broken 1100mah twist+wire+led+resistor+switch+time = practice for putting together my dna mod lol. supposed to be here tomorrow.

     
  16. ian-field

    ian-field Super Member ECF Veteran

    Dec 3, 2013
    Hertfordshire
    I can recommend the Allaboutcircuits forum - I vaguely remember seeing some links to e-books from basic electrical to about intermediate electronics.

    If you get stuck, just post a question on the forum.

    All About Circuits Forum - Powered by vBulletin
     
Thread Status:
Not open for further replies.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice