How to double battery life minimum weight added

Discussion in 'Switch - Tutorials' started by Migoma, May 15, 2018 at 9:48 PM.

  1. Migoma
    OP

    Migoma Advanced Member

    Newcomer
    2
    Mar 12, 2015
    United States
    Ever since the Switch was released my friend and i were very disappointed about battery life we ordered extended battery cases that made the switch twice as heavy but it was just not a good solution overall.

    So I ordered 2 NEW OEM Switch batteries from ebay,charged both to 100% and soldered the positive-negative together to run them in parallel then cut the metal shield with scissors and cut the back cover with a plexy glass cutter to glue one battery on top of the other and covered the exposed battery with vinyl

    The switch weights 476 grams vs the original 398 grams the battery last 5:30 to 6:00 gaming and it takes about 6 hours to charge thats the only downside.

    P_20180513_152925_vHDR_Auto.jpg P_20180513_153508_vHDR_Auto.jpg P_20180513_160820_vHDR_Auto.jpg P_20180513_164102_vHDR_Auto.jpg P_20180513_165623_vHDR_Auto.jpg P_20180513_171149_vHDR_Auto.jpg P_20180513_180243_vHDR_Auto.jpg P_20180513_192715_vHDR_Auto.jpg
     
    Last edited by Migoma, May 15, 2018 at 10:44 PM
  2. FAST6191

    FAST6191 Techromancer

    pip Reporter
    19
    Nov 21, 2005
    United Kingdom
    Straight parallel charge gets tricky. It can be done but I would want a management chip. If one battery is already slightly used (thus lower capacity, or otherwise lower capacity because manufacturing reasons) you start charging them at different rates or overcharging or something equally not so good for lithium cells.
     
    x65943 and cearp like this.
  3. Migoma
    OP

    Migoma Advanced Member

    Newcomer
    2
    Mar 12, 2015
    United States
    Yeah both batteries are brand new that i used.
     
  4. Reploid

    Reploid GBAtemp Advanced Fan

    Member
    5
    Jan 20, 2010
    Serbia, Republic of
    cool, but deformed
     
  5. FAST6191

    FAST6191 Techromancer

    pip Reporter
    19
    Nov 21, 2005
    United Kingdom
    Even so if there is a slight difference in input impedance (there will be, impedance matching is terribly difficult), different ageing in the batteries (if one has more heat dispersal than the other then it almost inevitably will) or something along those lines you start getting them charge and discharge each other.
    Absolutely do parallel things up if it comes at a weight cost you can deal with (Nintendo has to design it for the skinniest Japanese 5 year old after all) but make sure they are still managed. I imagine you have seen or even replaced a laptop with a single 18650 that tanked and took the whole thing down with it, almost same deal here). Alternatively a simple switch, possibly with a capacitor to handle switching overlap, will also do what you want if you can handle the multiple charge cycles or otherwise provide an external option.
     
  6. Migoma
    OP

    Migoma Advanced Member

    Newcomer
    2
    Mar 12, 2015
    United States
    true its very hard to match-balance batteries in parallel and there will always be differences i am working in a plug and play solution where I can externally charge the batteries and quickly attach them to the switch without adding much weight but in the meantime this will have to suffice.
     
  7. quazimojo

    quazimojo Member

    Newcomer
    1
    Feb 16, 2015
    United States
    Very cool. Battery life is so bad on the switch and all the external batteries are tanks. This is a nice happy medium and because you can buy a replacement OEM cover for $10 on fleabay if you ever want to get it back to stock then the cost is absolutely nothing.
     
    Migoma likes this.
  8. RedBlueGreen

    RedBlueGreen GBAtemp Maniac

    Member
    4
    Aug 10, 2015
    Canada
    Aren't Nintendo's batteries supposed to protect against overcharging?
     
  9. sarkwalvein

    sarkwalvein There's hope for a Xenosaga port.

    Member
    16
    GBAtemp Patron
    sarkwalvein is a Patron of GBAtemp and is helping us stay independent!

    Our Patreon
    Jun 29, 2007
    Germany
    Niedersachsen
    The charging circuit does that, but it expects one battery, not two in parallel.
    If you connect both in parallel to the on IC output, it has no way to control how much current goes into each one.
     
  10. nukeboy95

    nukeboy95 Old skool member

    Member
    5
    Aug 24, 2010
    United States
    The left side
    I'd be extremely careful with an exposed battery cell like that. A single scratch could result in a fiery explosion
     
    0x25b3 likes this.
  11. LucaFraga

    LucaFraga Member

    Newcomer
    3
    Aug 10, 2009
    Italy
    Cool idea, but this is looking for trouble:
    - Exposed cell, you need a solid shell to cover that battery
    - Parallel charging without a dedicated IC? They won't last very long.
     
    MichiS97 and Extrasklep like this.
  12. Hayato213

    Hayato213 GBAtemp Advanced Fan

    Member
    2
    Dec 26, 2015
    United States
    Not a good idea, higher chance of a fire due to chance of battery being exposed and heating on top of each other. It would just be disaster as compared to using an larger capacity battery.
     
  13. Taffy

    Taffy AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

    Member
    3
    Mar 3, 2017
    United States
    Student
    ...How do you dock it?

    Doesn't that stick out too much? Or did you slice the dock up?
     
    Migoma likes this.
  14. Migoma
    OP

    Migoma Advanced Member

    Newcomer
    2
    Mar 12, 2015
    United States
    Yeah I built a shell out of an external HDD caddy to cover the battery I'll let you guys know if it catches on fire while playing or charging


    I use a USB c extension all the time even before adding the battery.
     
    x65943 likes this.
  15. Migoma
    OP

    Migoma Advanced Member

    Newcomer
    2
    Mar 12, 2015
    United States
    Parallel batteries balance themselves the charger just gonna take twice as long to charge the same pack parallel batteries without a controller are a common practice and they last years the problem is matching the batteries with the same capacity
     
  16. smf

    smf GBAtemp Maniac

    Member
    5
    Feb 23, 2009
    Your main problem will be that you can now discharge one of them further than is safe.
     
  17. Migoma
    OP

    Migoma Advanced Member

    Newcomer
    2
    Mar 12, 2015
    United States
    How could I discharge one further if they are always balancing themselves that's only if one of them fails before the other
     
  18. FAST6191

    FAST6191 Techromancer

    pip Reporter
    19
    Nov 21, 2005
    United Kingdom
    If you are doing simple charging then maybe.

    If you are doing http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries and all the temperature managed charging (the nice external one flapping in the breeze, the original internal one blocked by both the case and the extra battery) and again if you have a different discharge rate (being wired and soldered it is less likely than simple spring contact but if even welded cells in laptops and tools hose this up...) then not so much. Said low resistance will also cut the other way though and if one cell does end up different for whatever reason (some kind of charge recovery or temperature masked voltage perhaps) then you all of a sudden end up whacking in a few more amps than you might care to. All of this is then negated by having a charge management chip for each of the cells, or a toggle switch to swap them out.
     
  19. The Real Jdbye

    The Real Jdbye Always Remember 30/07/08

    Member
    16
    GBAtemp Patron
    The Real Jdbye is a Patron of GBAtemp and is helping us stay independent!

    Our Patreon
    Mar 17, 2010
    Norway
    Alola
    That's only true if the batteries have integrated protection circuits. Many do, but whether the Switch ones do I couldn't tell you.
    When you measure the voltage to calculate battery charge level, you get the average of the two voltages.
    As an example, if one battery is charged to 4.15 and the other to 4.2, the 4.2 battery is fully charged but the voltage will be measured as 4.17-4.18, causing the 4.2 battery to be slightly overcharged until the average reaches 4.2, at which point the other cell will still not be fully charged, and charging will stop. Overcharging can damage or kill the cells. And the cell with slightly less voltage on it will never be fully charged. Also when discharging, the cell with slightly higher voltage will never be discharged fully, since it will cut off once the average reaches 3.1 or whatever the Switch has set as the cutoff point, and the cell with slightly lower voltage might be discharged below that level (but the safe minimum voltage is 2.5v so we should still be good there and it shouldn't harm the battery, unless the voltage difference is huge)

    This will cause the batteries to be worn unevenly, so the problem will get worse and worse.

    If the battery has a built in protection circuit, it will protect it from overcharging or over discharging. However, if the batteries are of slightly uneven capacity to begin with or aren't charged to the exact same level, then you'll still not get the full capacity of each battery as you'll still have problems with charging cutting off before every cell is charged, and similarly the Switch shutting off while one battery still has some juice left in it, and that problem will still get worse over time, at least you won't be damaging the batteries though, merely lowering the apparent capacity of them because they're not being utilized fully.
     
    Last edited by The Real Jdbye, May 16, 2018 at 11:42 PM
    cracker likes this.
  20. smf

    smf GBAtemp Maniac

    Member
    5
    Feb 23, 2009
Loading...
  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