No need to apologize for being a noob. All of us where noobs starting out. that’s a really nice JST-XH chart. It looks correct but I would still double check my balance wires with a voltage meter. This BMS does not use the Black ground balance wire from the Lipos as illustrated in my diagram. The BMS balance jack is numbered on the bottom side of the PCB. My updated diagram show the bms layout as it is on the real thing.
There is one more important point that I almost forgot to mention: These modules are static sensitive so you need to have some type of static protection before you open the bag and remove them. I use these wireless wrist bands. They seem to work well. They absorb any static charge that is on your body.
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I have a lot of experience with RC cars but I am new to eskate. After reading a lot I have the feeling that 10s 5000mah lipo performs as good as 10s3p liion and almost like 10s4p.
That shouldn’t be that way because 10s4p with Samsung 25NR is twice the mah but in practice this looks true… Anyone else have the same impression???
Those are pretty good, I have one similar that I got from Battery Supports. It charges the pack fairly quick but cant quite charge the pack fully to 42v. It does get the pack up to 41.8 or 41.9 before getting the green light. The only other option is to use an Adjustable CC/CV lab power supply. Which is what I use. I like to get my pack fully charged for maximum performance and range and I am less concerned about their longevity.
Well, If you buy quality Lipos with high C rating then Li-ions can not compare is performance per pound. Example: My packs are 10s 5000mah 60/120c Thats a rating of 300a continuous and 600a peak A li-ion 10s3p is only 60a continuous a 10s4p is only 80a continous So, some may ask why would you need a 300a battery? The answer is VOLTAGE SAG. With a 300a battery, there minimum voltage sag under demanding conditions. With a 60-80a battery you will see much more sag under the same conditions. On top of that, the 300a Lipo pack is smaller and lighter than the 80a Li-ion pack. Some feel that Lipos are too hazardous and I for one have said as much. But recently I am finding that Li-ion cells can be just as hazardous.
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Yes you can but the bms will not power the light. You will need a volt/ohm meter to test continuity and find the 2 poles that connect when the button is on and connect the E-switch wires to those 2 poles. then find the 2 poles that energize the light when the switch is on and connect those to pos and neg 5v source. I used an open channel on my receiver to power the light on my switch. It is ultimately powered by the 5v coming for the Vesc.
Adding to @Namasaki here, Performance is relative. Are you measuring performance with range, power output, efficiency, or something else???
If we talk about range, the 10S4P is better as you have more energy. 360Wh vs 185Wh in the LiPo If we talk about power output, the 10S 5000mAh LiPo is better as they are designed to run at high power conditions, you’ll see this in the power ratings. (18650 cells rated between 1.5C-10C, while LiPos are rated between 25C-120C) The LiPo is smaller (8.4% smaller in volume) and lighter (17.2% in weight), but that is only because it has about half the energy than the 10S4P pack. If you compare two packs with identical energy the LiPo will be much heavier and bigger.
25R cells are pretty terrible cells in my opinion, the only good thing about them is that they’re cheap and really they’re not that cheap…
I suggest you use 30Q cells.
- They have 3000mAh which means a 10S4P pack will have 432Wh, which is 20% more than the 25R and 134% more than LiPo.
- They have much lower voltage sag than 25Rs which means you can push your board as much as you want without it cutting out on you.
- Can be found under $4 per cell.
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I am running the same battery pack but a single 6374 and a vedder e-switch+ big hobby charger. I am wondering what kind of range you are getting on a charge, and how long it takes the BMS to charge from empty to full? Is it charging at like 2A?
When I said performance I am referring to power and the ability to deliver high current without excessive voltage sag. I refer to range as range not as performance. So, theoretically, a 10s4p li-ion pack will have more range especially with 30q cells capable of 30a per cell. I did recently built a Li-ion pack using 26650 cells that 4500mah and capable of 30a per cell. My pack was a 10s2p so 9000mah or 324WH vs my 185wh Lipo pack. The Lipo pack is smaller and 1 pound lighter than the Li-ion pack. In demanding conditions with lots of hills, the range of the Li-ion pack was the same or less that the Lipo pack because voltage sag robbed the Li-ion pack of its range. Granted, on flat ground at moderate speeds the Li-ion pack had much more range. Unfortunately for me, most of my riding is up and down hills.
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I’m using a 5a charge so it’s pretty fast. Bout the same as a hobby charger.
Performance can be measured based on need. I won’t argue how you decide to measure it.
A 30Q 10S4P pack can deliver 1680W of power throughout 91% of it’s capacity and 2000W through 83% of it’s capacity. I’m using 2.8V as the cutoff when they can really go down to 2.5V. The 25Rs on the other hand can only do this for about 50% of their capacity. So I believe that a 25R pack in a high power environment only had as much range as your LiPo Pack (this is why I think they are crap), the 30Q pack on the other hand would still have twice as much range if you constantly ran it at these power conditions.
My 10S4P pack weighs 4.375lbs including all wires and connectors, according to the link in your first post 5 of your cells weigh 3.46lbs, so lets assume 3.5lbs once all is done. That is 20% lighter than the Li-ion, so 3% off of my initial estimate.
My 26650 pack was very disappointing, I had my meter mounted through the deck so I could monitor it while riding and saw my battery drop 30-40% in voltage sag while climbing a 10% grade.
What cells were you using?
I can go 9-10 miles on a charge with identical batteries and different combo.
I’m getting 10 mi with hills. Haven’t done the moderate speed flat ground test yet.
Yup, your conversation pretty much confirms my theory. A 10s4p has two times more energy but in practice, using it on street, gets pretty much the same range :S
huh? 10characters
After reading many topics on the forum I was feeling that people on 10s 5000mah lipo were having the same range than 10s3p and almost like 10s4p
Namasaki just said that he is getting same range on his 10s3p 9000mah liion than in his 10s 5000mah lipo
Have you also asked people on their VESC cut-off values? Liions should be ridden with a VESC cutoff at 3V while Lipos typically are only used until 3.4V. There is a lot of Energy left if you keep your Lipo settings and just switch to a Liion battery.
I have not, as I said it is just an impression that I have and feels weird even to me but what Namakasi said can be true… Liion have a huge voltage sag on high demand of power and that can cut drastically its range