Announcement

Collapse
No announcement yet.

Parallel adapter for doubling battery capacity

Collapse
This is a sticky topic.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 73Eldo
    replied
    There are BMS's that do not have a separate charge port but that's not the common style in E bike land. 'Two wire' BMS is the common term for the type that don't have a charge port and 'three wire' are the ones with a charge port. 2 wire generally cost more is one reason you see lots of 3 wire.

    Leave a comment:


  • ncmired
    replied
    Originally posted by evodev View Post
    This guy seems to think you can charge a Luna Shark Pack through the discharge port. https://www.youtube.com/watch?v=6hIYB0O1hlY
    I don't think "charging" is what he's after here - his intent is to reset the BMS. See his follow-up comment, "This is only for testing and/or resetting the battery management system. If the battery is not accepting a charge via the normal charge circuit you need to figure out why. Charging through discharge is not recommended for anything besides troubleshooting as it basically bypasses the safety protections built into the BMS".

    Leave a comment:


  • AZguy
    commented on 's reply
    Can and should are *very* different things

  • evodev
    replied
    I would like to try the charging version of this device that says you can use one charger to charge both batteries, but has a warning "Please, ensure your batteries are able to be charged via their discharge port if you purchase a DATEx2 device with charge function!"

    I have a Luna 48v Shark Panasonic Battery pack. I was thinking of getting another. Do you think these batteries can be charged from the discharge port?

    This guy seems to think you can charge a Luna Shark Pack through the discharge port. https://www.youtube.com/watch?v=6hIYB0O1hlY
    Last edited by evodev; 04-27-2021, 01:47 PM.

    Leave a comment:


  • paxtana
    commented on 's reply
    Looks interesting. If you try it would like to know how well it works.

  • evodev
    replied
    Have you seen this product? I just posted about it in the batteries forum, wondering if it would be safer? It seems like a game changer. I've never heard about it before, so I'm not sure.
    https://biggamebikes.com/product/dat...ttery-adapter/

    Here is a video: https://www.youtube.com/watch?v=pvumfnCff10

    Leave a comment:


  • paxtana
    replied
    You should not charge in parallel.

    Leave a comment:


  • Joelo
    replied
    If I have two brand new batteries (72v 10Amp/hr Panasonic fat tri.). Should I charge them in parallel always, to keep them equal? Maybe heat shrink the connector and battery together as one.

    Leave a comment:


  • geekazoid
    replied
    Originally posted by MikeG6.5 View Post
    I'm still working out the details on this, and have come across something that looks like it may work.

    After talking to Josh from Mouser.com we found this part: https://www.mouser.com/ProductDetail/STMicroelectronics/STPS80H100TV?qs=%2fha2pyFaduh5Z9zu%252blo7FyfMDj9T NIW5dDZ0s%252blJb91DOUcxrVHfQQ%3d%3d which has a 100V Maximum voltage across the unit, and a maximum of 40A per side of the diode. With the two sides on it, it can handle a maximum of 80A, which is a lot higher than my motor could even think of drawing. (It helps talking with someone that's more current on electronics than my HS electronics classes from 30+ years ago.)

    Connect one battery to the "left" anode, the other to the "right" anode, and the motor power connecter to both cathodes. The batteries are isolated from each other and the motor/controller can draw from each pack equally. The rider can still use just a single battery with this in-line if so desired. Or you can run both batteries for extended range without them cross-charging each other.

    The diode package is about 1.5" long, 1" wide and less than .5" thick.
    Cost of the diode is about $25/unit when bought individually. Bought in bulk I would guess the prices would be less. Not sure what this would work out to for a retail pricing.

    I'll be testing this in a couple of weeks, and will report back what I find here.
    MikeG how did this work out? I'm about to order one.

    Leave a comment:


  • paxtana
    commented on 's reply
    Only adapter we have is the xt90 parallel. That's two in parallel not three. Also don't know what sort of connector you have on the lipo, but given that we do not have any adapter for putting three in parallel you would probably have to make it or google for a parallel adapter that connects three of whatever connector you are using on the lipo packs.

  • dlytton
    replied
    I need an adapter to parallel (3) 6S Lipo Batteries. By change does Luna make those? Thank you!!!

    Leave a comment:


  • New Mariner
    replied
    Originally posted by MikeG6.5 View Post
    I'm still working out the details on this, and have come across something that looks like it may work.

    After talking to Josh from Mouser.com we found this part: https://www.mouser.com/ProductDetail/STMicroelectronics/STPS80H100TV?qs=%2fha2pyFaduh5Z9zu%252blo7FyfMDj9T NIW5dDZ0s%252blJb91DOUcxrVHfQQ%3d%3d which has a 100V Maximum voltage across the unit, and a maximum of 40A per side of the diode. With the two sides on it, it can handle a maximum of 80A, which is a lot higher than my motor could even think of drawing. (It helps talking with someone that's more current on electronics than my HS electronics classes from 30+ years ago.)

    Connect one battery to the "left" anode, the other to the "right" anode, and the motor power connecter to both cathodes. The batteries are isolated from each other and the motor/controller can draw from each pack equally. The rider can still use just a single battery with this in-line if so desired. Or you can run both batteries for extended range without them cross-charging each other.

    The diode package is about 1.5" long, 1" wide and less than .5" thick.
    Cost of the diode is about $25/unit when bought individually. Bought in bulk I would guess the prices would be less. Not sure what this would work out to for a retail pricing.

    I'll be testing this in a couple of weeks, and will report back what I find here.
    would a lower voltage and lower amp diode be less expensive?

    Leave a comment:


  • MikeG6.5
    replied
    In a way. Most of the diodes we talked about had current and voltage limits that were borderline. For example, 60V but max 30A for both legs (15A/leg) in a "flat pack" design. This would require 1 diode for each battery pack, and would ultimately be more expensive than the one I linked to above. ($16-$19 per diode. so at least $32 for 2 batteries.) For those with the room for more than 2 packs, these smaller diodes wouldn't work if trying to connect 3 or 4 to the controller.

    This one, while a bit more expensive for a single device, fits the voltage and current for at least my use case. (Bafang BBS02 with 48V battery packs.) It it's all in just one set of connections. (One from each battery and then combining both outputs to your motor/controller.) The size of this isn't much more than the size of the connectors themselves. Once the whole thing is made up, wrapped in some heat shrink, and there it is.... Unlike other diode examples, this could be used to connect a 3rd or 4th battery in parallel. A 3rd diode would be needed for 3 or 4. The input for each battery on two diode sets, and their outputs feeding the inputs on the third diode. (This would be for trikes or bikes with trailers or cargo options. Probably not for DF bikes, unless you have a lot of space for batteries.)

    If the motor/controller draws no more than 40Amps, the 3rd diode should be safe from blowing either of the two legs. (And this would be the weakest spot of the whole design, I would think...) You could fuse each battery, or run a single fuse after all the packs are hooked in parallel. Remember, at this point it's all theoretical... No one has actually done this and reported on it here, yet... (Or if they have, I haven't seen it.)

    Leave a comment:


  • Fred
    replied
    Very interesting. Is there any difference other than packaging between this and using 2 separate diodes and wiring them up the same way?

    Leave a comment:


  • MikeG6.5
    replied
    I'm still working out the details on this, and have come across something that looks like it may work.

    After talking to Josh from Mouser.com we found this part: https://www.mouser.com/ProductDetail/STMicroelectronics/STPS80H100TV?qs=%2fha2pyFaduh5Z9zu%252blo7FyfMDj9T NIW5dDZ0s%252blJb91DOUcxrVHfQQ%3d%3d which has a 100V Maximum voltage across the unit, and a maximum of 40A per side of the diode. With the two sides on it, it can handle a maximum of 80A, which is a lot higher than my motor could even think of drawing. (It helps talking with someone that's more current on electronics than my HS electronics classes from 30+ years ago.)

    Connect one battery to the "left" anode, the other to the "right" anode, and the motor power connecter to both cathodes. The batteries are isolated from each other and the motor/controller can draw from each pack equally. The rider can still use just a single battery with this in-line if so desired. Or you can run both batteries for extended range without them cross-charging each other.

    The diode package is about 1.5" long, 1" wide and less than .5" thick.
    Cost of the diode is about $25/unit when bought individually. Bought in bulk I would guess the prices would be less. Not sure what this would work out to for a retail pricing.

    I'll be testing this in a couple of weeks, and will report back what I find here.

    Leave a comment:

Working...
X