I was wondering if anybody has added balance ports on the exterior of battery packs. It would be good to be able to swap a Active 100balance module to various packs to save opening the packs up?
Battery Balance ports
- Thread starter Garry Hallam
- Start date
That's effectively what you have when you use R/C lipos, or you can use a BC168 charger to charge the cells individually 6 at a time. It's basically 6 1S chargers in a box.
10 to 12 years ago, it was quite common to see a paralleled multipin connector, presumably for testing, but could also be used for balancing.
Yes I have flown RC too. I just seems to be a reasonable and feasible way to do Ebike packs too. Especially given the cost of these things! I would imagine for safetys sake too.
Not an issue to add an exterior set of sense wires , though the jst will need protection from moisture . Easy for a home made diy pack (soft case ) contained with in a battery zip case but not so for a hard shell case where wirng and jst are out of view.
For the most part balancing isn't needed with lion cells if one charges correctly with a BMS fitted.
For the most part balancing isn't needed with lion cells if one charges correctly with a BMS fitted.
Had similar thoughts until i saw the price of 10x cell chargers, they exist but omg not cheap, i was kinda hoping a similar budget charger to my upto 6cell job was available but no..
Was wondering if a dsub 15 would work. It seems they are more than capable of handling 36v 1a. Then a case of just wiring the pins needed. You can get waterproof covers for them also.
Dsub seems ideal but I haven't found a straight through 15 way cable yet, VGA cables have certain pins connected in the plug and <15 cores. Be wary of sharp edges when routing the internal connections!
I was thinking that I would make up the cable myself with a dsub male from the balancer using the original wire from that. 100 balance modules claim that thier wire cannot be substituted for some reason? And after reading the previous post using ptfe or other high temp wire inside the case to the dsub female. But then that is not original wire
You can use any wire you want as long as it's guaranteed that the conductors will never touch, otherwise, you'll be looking for a new residence.
Which has me thinking even further in depth about adding fuses on all outs from the battery terminals and between each cell group just for safetys sake. Was thinking glass fuses and soldering directly to that and heat shrink. Surely then if any condutors in the wiring were to short then it would be a fail safe. I think I have OCD. These things petrify me!
How much safer are Lifepo4 cells? I am seriously thinking about dumping both my packs and getting those instead
Most of us just buy a battery, charge it, use it and repeat for years until it starts to get tired. I don't get why you guys are always inventing ways to make it more expensive and more complicated than it needs to be. I've never hear of anybody wanting to add balance ports to their power drill, lawnmower or vacuum cleaner, neither have I seen people buying special chargers and inventing new charging procedures for them. Why do they do it for ebikes?
Cannot speak for anybody else, but In my case it would stem from having flown radio control model planes and using lipo batterys. They always come with balance leads built directly into the battery for anything over 1S and is super important that those lipo cells are balanced correctly or they can get funky. I guess you are saying that balance in lithium 18650 packs is not important or if they do get out of whack?
I will be honest and say that it was after deciding to build my own pack that I started to wish I hadn't done so. I live in a flat and cannot store my batterys outside. I would have to run down 2 flights of stairs if anything went wrong with charging etc!
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Lipo have no BMS so need the balance wires for charging/balancing (unless like me and modded 8s and 4s lipo wiring for 12s and added a BMS , simply for the conveneance when charging ).
Lion don't need balance wires as they don't go out of whack if normal and correct charging practices are followed. With Lion there is no need at all to only 80/90% percent charge for life cycle as one won't see much benefit at all.
Lifepo4/LFP are great for static or larger vehicles , for bike use they are a bit too heavy and were tried some 10 years ago . The carrying of excess weight doesn't make sense with lion cells available.
Lion don't need balance wires as they don't go out of whack if normal and correct charging practices are followed. With Lion there is no need at all to only 80/90% percent charge for life cycle as one won't see much benefit at all.
Lifepo4/LFP are great for static or larger vehicles , for bike use they are a bit too heavy and were tried some 10 years ago . The carrying of excess weight doesn't make sense with lion cells available.
That makes sense. But after reading lots of reviews online I had come to the conclusion that the majority of bms used in commercialy available battery packs are not very effective at actually balancing the pack and that active balance add in modules make up for this shortfall.
I assume however that the final voltage achieved at the end of charge gives an indication as to the balance state of the pack.
There seems to be a lot of scare mongering on the dangers of lion and for those of us with OCD it can be rather scary
The more complicated you make something, the more likely it is to fail. OEM batteries are fine. You don't have to do anything. Just charge and use. That's it.
Tbh lion will keep to within 0.01v- 0.05v which is ore then adequate , they aren't so fussy like lipo . Most generic BMS are fine in lion and will happily look after the battery cells, every now and then ther eare failures but there are millions of these things in use so one has to expect a failure now and then.