Why is my range so low? 10s 4000mah lipo battery

Hi so I just finished my electric skateboard the other day and I’ve fallen in love with the thing. (( think metaphorically here not literally love)) But I have one slight problem…it only lasts for about 3 to 4 miles before the cheap SEC turns itself off for safety purposes. My problem is I want to ride it to work and back without having to swap a new set of batteries out mid commute. Its not a high powered motor its a cheap hub motor from ebay I also got these 2 lipo’s and here is myESC But again I’m only getting 3 or 4 miles of range out of this set up. I’m woundering if I make my own 18650 pack and maybe a smaller motor like this one will dropping the voltage and making a bigger battery would it help at all? pleast help!

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That sounds about right for 10S 4Ah. If you put two more of those batteries in parallel, it will double the range (10S 8Ah)

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First off, that esc is crap. second, your battery mah is the main reason you’re getting so little range. buy 2 more and put them in parallel. Oh i see @b264 beat me to it :sweat_smile:

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Don’t use 260kv motors though. Use 190kv at the highest. 140kv to 190kv.

what would be wrong using that motor? also if I drop the voltage and make my own pack would I expect more range? I was thinking of starting another build and use the battery’s I have for an Arduino spot welder. I live in an apartment with dated electrical so I don’t want to buy one of those cheapo spot welders.

If/when you want to upgrade your ESC you won’t be able to without buying a new motor. Plus when the kv is over 190 they have little if any resale value on the used market. Trust those who have trodden before you. Don’t go over 190kv :wink:

The same motor is available for the same price wound at 190kv instead and those are good motors. I’d put acrylic conformal coating on the sensor assembly though otherwise it’s not water resistant.

ok sounds like ill be using that motor then. But to ask would lowering my voltage and building my own 18650 pack do anything for range? I want to stay between the 20-30 MPH range and about 10-20 miles in range. so i was thinking maybe a 6s 4p pack would do just that.

Lowering your voltage won’t increase your range. Adding amp*hours of course is the ultimate range-extender. Limiting motor current (in software) will increase your range too. But the single biggest thing that will increase your range is learning how to pilot the esk8 in a way that is much more efficient.

I suggest limiting the motor current in software, seeing how it rides, then turning it back up and trying to ride the way you remember it felt most of the time. Then occasionally you can hit the throttle hard if you want… but for the most part you just feather the throttle enough to keep you moving. Also kicking to start can help a lot with extending range.

But with that ESC, you can’t adjust anything at all. But the rest is still do-able.

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well thanks for the info. It helps out a lot! :slight_smile: i will look into upgrading my ESC here soon. I might go with a dual vesc set up. im already thinking of my next build as it is! Thanks! :smiley:

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Of course you are my friend

welcome to the hotel california. Its an addiction make no mistake.

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Buy the best ESC if it’s possible (Vesc6, Focbox, etc…), 130kv - 170kv…No need for twin set up if you can not afford a great ESC, but with one VESC6 for example, you could go 12s 4P (2 x 6s 2P 22000mAh each)…Just try not to waste money…Read a lot, learn a lot, then spend a lot… Enjoy!!!

For batteries its best to think in terms of watt hours, amp hours is only a fair comparison for batteries of the same voltage. Take the amp hours of the pack and multiply it by the nominal voltage to get the watt hours. For reference a good 10s4p Li-Ion pack will have somewhere around 400-450 Watt hours capacity and that will get you somewhere in the 20 mile range if your lightweight and riding efficiently. Your pack is 37V * 4 Ah = 140 Watt hours, so about 1/3rd the size if the Ah rating on your lipos can be trusted.

Unless you plan to make/weld multiple batteries I would strongly encourage you to simply buy one off the shelf. I’ve done some cost breakdowns on this and even if you don’t mess anything up and make a perfect battery each time you have to make a few before you recoup costs on all the equipment (time, BMS, nickel strip, cells, shrink wrap, wiring etc.). You can even just slap two meepo batteries in parallel if your low on funds and want a cheap solution, the form factor isn’t the best though and if you look around on the forum here you’ll find some other competitive offerings.

@b264 is steering you right on lower kv motors, additionally I wanted to add in some extra info that may be somewhat counter-intuitive. The bigger the motor used (more copper) the more efficient that motor will be IF you ride the board conservatively. Very different from how gas cars work here, big beefy motors ridden gently will get the most efficiency.

Also since I’m me, let me shamelessly plug the new focbox unity! It’s a great dual setup and includes power switch/bluetooth and app and offers all the customization of vesc based designs. It’s nice because it is an easy swap out for your existing controller without any more wiring/parts. Perhaps a bit pricey, but its the brain of your board and the unity will be able to handle pretty much anything in your upgrade path. If you need something cheaper I’d stay away from the flipsky dual 4.20 esc, a lot of reported issues there. Better off going with some of the other cheap alternatives like hobbyking or something, just be aware they won’t be able to push the same amps since they have no dedicated heatsink attached and use cheaper components.

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Upgrading to a Unity or other similar ESC based on VESC technology should definitely be in your long-term plans.

6374 will be more efficient than the 6355 but they are also rather heavy and kind-of overkill. In my honest opinion, dual 6355 are perfect for esk8. 6374 maybe for a performance build, but they also add a lot of weight for a minimal amount of gain relative to the cost/weight/space increase.

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one thing i want to add here too, just that it´s said. there some things besides your weight and riding style which influence your range. if you use pneumantic wheels it will decrease your range about 20%. Also which drive train you use. I don´t have experience with direct drive or hubs yet, but i can say chain - belts - geardrive in this order your range will expand. for example i got about 10km out of a 12s 5Ah pack with a belt drive train. than i changed to chains and now my range is only about 8-8,5km

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Not sure how this went so wrong. Your batteries are the main problem, not your motors and esc.

With those batteries you could expect somewhere around 10km of range. I have a dual chain board with a 12s5000mah battery (222wh) and I can get anywhere between 20 and 12km of range depending on how I ride. I also have a single board with 10s5000mah battery, that board gets between 20 and 15km of range.

Now you have a 10s4000mah battery (148wh) with the average wh usage of 10wh/km you would get something like 15km of range. That isn’t accurate unless you ride under 20km/h though. I like to use 12-14wh/km as my rule as it gives some more room for faster riding. According to that you should get about 10km of range. But if you ride at top speed constantly you will probably only get 7-8km.

If you really want long range you need to listen to others and get a li-ion pack, something like 10s4p or even 5p. Otherwise just don’t ride so fast all the time, I know it’s hard at the start I used to gun it the whole ride, but now I prefer to cruise about 25km/h and enjoy carving and the scenery

Long range is definitely possible without a li-ion pack. LiFePO4 or LiPo can definitely get long range.

I think it’s mainly riding style and mAh

hey @pat.speed how you manage to get 20km out of that with chains? you have chains and pneumatics or urethan? i once got like 17km out of my 12s 5Ah packs but with belt and the average speed was about 8-10km/h :sweat_smile: maybe i make something wrong :thinking: or maybe i shouldn´t go so hard offroad :rofl:

I ride thanes and only weight 60kg so that def helps, I came back from a ride the other day, we did about 17km and my cells were at 3.65v so I could easily squeeze out a few more kms.

@b264 yeah I agree lipos can also be used for longer range, I personally think it is just easy to use a 18650 pack when you need one that big. The tangle of wires from lipos in parallel would drive me crazy

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The stated Ah for a cell is determined by measuring at a low current draw and down to a lower voltage level than the cut off value we usually use on our boards, so to get a better estimate of range one should have that in mind when calculating Wh.

A 10s4p of 30q cells will more likely have around 330 usuable Wh in our applications.

10S 4Ah so around 150Wh, those lipo’s must give you at least 11km (7miles) range. The esc an hubmotors pull around 20A max so if the lipo’s are good that shouldn’t be a problem. The only thing I can imagine why you get such a low range is voltage sag, maybe these batteries are not as good as described.

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