Results 1 to 14 of 14
  1. #1
    RC Racer
    Join Date
    Aug 2012
    Location
    San Jose, California
    Posts
    120

    When to recharged our LiPo's

    My son and I received our new 2S LiPo's yesterday (Tuesday). Charged both and went out with our Stampede's. I lost a pin in my MIP axle after 10-15 minutes. My son played with his for about an hour before having to go in. Neither battery was discharged to the point that the ESC cut them off.

    My question is, do I just throw them back on the charger and bring them back up to 100% to use tomorrow (Thursday)? Or just leave them as is and use them until the cut off point and then recharge them afterward?

    Thanks

  2. #2
    Marshal ksb51rl's Avatar
    Join Date
    Nov 2006
    Location
    Northern NJ
    Posts
    15,885
    What Traxxas has to say on the subject:
    Storing Your Batteries
    ...LiPo batteries should be stored at 50% capacity. Store LiPo batteries in a charging bag or case. Do NOT store LiPo batteries discharged, as this will reduce battery performance and may lead to over-discharging if the packs are stored discharged for an extended length of time. The Traxxas EZ-Peak Plus makes it easy to store LiPos properly; just recharge the pack using Storage mode and it will charge the pack to 50% capacity.
    Alt-248 on the number pad =

  3. #3
    RC Turnbuckle Jr. mike-susieq1's Avatar
    Join Date
    Nov 2010
    Location
    California
    Posts
    4,840
    As posted your charger should have a storage charge mode. Use it and when it beeps its done ready for storage i do this even if I plan to use my lipos the next day.
    DEU 8:18 ESV

  4. #4
    RC Turnbuckle Jr. 87 GN's Avatar
    Join Date
    Mar 2010
    Location
    kansas
    Posts
    7,894
    I store batts at about 3.85v per cell, if not going to be used for a couple of days..

    Don't leave them fully charged for more than a day either...

    All JMHO.........
    Would you go flip my truck back over??

  5. #5
    RC Turnbuckle Jr.
    Join Date
    Dec 2006
    Posts
    4,399
    Quote Originally Posted by ksb51rl View Post
    What Traxxas has to say on the subject:
    Well, saying 50% seems wrong and inaccurate to me... What does it mean to charge a battery at 50%? Suppose you have a fully charged 1-cell LiPo battery (4.2v) and you charge it at 50%, that's 2.1v, and that will destroy your 1-cell LiPo battery, which should never go bellow 3.0v per cell... Traxxas should say, charge your LiPo up to 3.7-3.8-3.85v per cell for storage...
    Last edited by danielhr77; 10-13-2012 at 07:37 PM.

  6. #6
    Marshal ksb51rl's Avatar
    Join Date
    Nov 2006
    Location
    Northern NJ
    Posts
    15,885
    No battery's capacity is measured from 0 volts. Some basic understanding is always necessary when using power sources. Traxxas is correct in its instructions.
    Alt-248 on the number pad =

  7. #7
    RC Turnbuckle Jr. mike-susieq1's Avatar
    Join Date
    Nov 2010
    Location
    California
    Posts
    4,840
    to clearify what voltage would you measure at starting the 50%? just so everyone and the OP can know. I use the factor of 3.85v or 3.80v per cell.
    DEU 8:18 ESV

  8. #8
    RC Turnbuckle Jr.
    Join Date
    Dec 2006
    Posts
    4,399
    EDITED: not going to argue, I'll let the OP google the info and find out what's the right 50% in volts.
    Last edited by danielhr77; 10-14-2012 at 12:01 AM.

  9. #9
    RC Competitor
    Join Date
    Dec 2010
    Location
    J-town, NJ
    Posts
    91
    I have to agree with ksb. Assuming you run your lipo to cutoff, 3.2v-3.4v, putting in %50 of the used voltage brings you right to storage voltage. I'm sure traxxas also spells out somewhere that lipos aren't meant to be run to 0v, don't run below cutoff, etc. It's pretty basic if you do some reading, be it in the manual or online.
    Edit: To the OP, all lipo chargers have a storage mode, charge to that and you're good.

  10. #10
    RC Turnbuckle Jr.
    Join Date
    Dec 2006
    Posts
    4,399
    EDITED: same reason as before.
    Last edited by danielhr77; 10-14-2012 at 12:00 AM.

  11. #11
    RC Competitor
    Join Date
    Aug 2011
    Location
    Drammen / Norway
    Posts
    70
    Have the tread started got his question answered ? If you have lowsaturn, pay no further attention to this. If not, keep on reading :-)

    I'm no lipo guru by all means, but to keep it simple, when you get a new lipo, it should be at arround 3,80-3,85 v pr cell. If not then something is wrong with the pack. One cell reading 3,45 and the other 3,80 as an example. I always check , either at my charger ore with a handy little device like in the pic's the V of a new pack before I solder on any deans/ec5 etc.






    Anyway, as you asked if you should charge them up after a 10-15 min run, I don't see why not, ore why. Should be plenty of juice left for some more play time , ore while fixing the car, why not charge them up again :-) I myself like to have a few packs ready, so I have a 3 day window , if I charge on sunday, but don't get the time to drive, I get them into storage V again by , say , wednesday. never had a problem with that. When you get the ba... you can try parallel charging. get one of them ready parallel boards and keep the lipos same brand and cells , and you are good to go.


  12. #12
    RC Turnbuckle Jr. mike-susieq1's Avatar
    Join Date
    Nov 2010
    Location
    California
    Posts
    4,840
    Quote Originally Posted by maxstian View Post
    Have the tread started got his question answered ? If you have lowsaturn, pay no further attention to this. If not, keep on reading :-)

    I'm no lipo guru by all means, but to keep it simple, when you get a new lipo, it should be at arround 3,80-3,85 v pr cell. If not then something is wrong with the pack. One cell reading 3,45 and the other 3,80 as an example. I always check , either at my charger ore with a handy little device like in the pic's the V of a new pack before I solder on any deans/ec5 etc.






    Anyway, as you asked if you should charge them up after a 10-15 min run, I don't see why not, ore why. Should be plenty of juice left for some more play time , ore while fixing the car, why not charge them up again :-) I myself like to have a few packs ready, so I have a 3 day window , if I charge on sunday, but don't get the time to drive, I get them into storage V again by , say , wednesday. never had a problem with that. When you get the ba... you can try parallel charging. get one of them ready parallel boards and keep the lipos same brand and cells , and you are good to go.

    There is alot more involved in parallel like the same cell count as in 2s can only be charged with other 2s lipos (no 3s/4s/5s/6s allowed) they need to be within voltage of eachother and same age and cycles on each pack, also the brand thing doesnt have to be done you can charge say spc, gensace, smc lipos all on the same parallel board with what i posted of course. you should charge in a safe spot or in a fire proof container incase anything happens as the charger reads only 1 large battery so if the cell voltages are way out of it you wont know. I would do research and more research before attempting parallel charging ok.
    DEU 8:18 ESV

  13. #13
    RC Competitor
    Join Date
    Aug 2011
    Location
    Drammen / Norway
    Posts
    70
    I see it was maybe a bitt hasty about the parallel charge. So listen to Mike.

    I have been doing it for a few years now, but I have kept it at 2 packs only at the same time( I made up my own charging and balancing leads before all those new boards you get now to hook up many packs at the same time came on the marked)also keeping it to same brand, same mah , same voltage same useage of packs( no mix of well used and brand new) and used a lipo bag.

    The fine thing about this is that you, if you have the power , you can cut the charging time by a good margin.

  14. #14
    RC Competitor
    Join Date
    Aug 2011
    Location
    Drammen / Norway
    Posts
    70
    dobb post.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •