S18XL - custom version with 20s4p 2170 battery setup

[Lukasz]

Hello all! As You know the Kingsong S18 is really nice wheel with suspension. One of the main drawback of this wheel is the small battery - build from 60 pcs of 2170 cells in the 20s3p setup. This can be quite dangerous, especially in winter when Li-Ion cells are cold and they can not provide enough current, creating risk of cut-out or quick battery degradation due to too high current draw / voltage sag. I have solved this problem by creating first in the world S18 with 80 cells - so proper setup for such 2200W motor - 20s4p setup build from original cells (complete battery packs) from Kingsong - by adding 2 additional rear packs on the front of the wheel. This is possible as due to specific construction of S18 each battery has its own BMS - so it is relatively easy to do this. This is just technical preview - wheel still needs customized front panels which I will design and produce for this wheel, also integrating them with front acceleration pads. 

Warning! "relatively easy" for skilled technically oriented person with proper tools and free time.

Always take caution when working with Li-Ion cells as You would with tank full of gasoline!

This is presented "as is" - this mods is not supported by Kingsong, no warranty of any kind is provided, and this mod may void Kingsong warranty. This works and is fine for me, but may not work and not be OK for You so please be careful. 

Please subscribe to my YT channel - thank You!

 

 

Edited September 14, 2020 by Lukasz

[Beachboy]

Hope you can make the battery kind of modular tho..but dont mind me, just wishful thinking..😅

[Jappierre]

I really like this idea. Hope we can buy this upgrade when it will be available.

Awesome job

[redsnapper]

very impressive mod but are you not concerned about the batts being outside the shell and effect of crash with direct impact on the batt box? or possible water intrusion into the batt boxes. I would just worry about possible negative outcomes with batts in that position... Again very nice mod though!

[Lukasz]

The battery is modular - S18 has normally 4 independent batteries - two of them - 84V build from from 20s1p setup - each battery has its own BMS on the front of the wheel, and 2 small packs 42 V also with idividual BMSes each which are connected in series creating third "p" 

In my mod I have added 2 pcs of original small 42V batteries connected in series + in parallel to the  existing third row creating 80 cells setup.

  

[Lukasz]

On 9/22/2020 at 2:26 AM, amelanso said:

very impressive mod but are you not concerned about the batts being outside the shell and effect of crash with direct impact on the batt box? or possible water intrusion into the batt boxes. I would just worry about possible negative outcomes with batts in that position... Again very nice mod though!

I am very concern, that is why I have already designed battery covers integrated with side pads in order to protect the batteries from being heavily hit in the fall.  I have added also small front bumper to protect front of the wheel and allow to park it in this way - as in general S18 has center of gravity relatively high and has the tendency to fall if left by the wall. YT video will be ready in a few days as I have to test the project and internally approve it - there are several small mods needed to make this whell road read in full. I have made today over 20km trip - city ride but rather high speed - up to 43km/h and came back with 75% of the battery. Key feature of this mod is not the range, but to protect the cells under heavy acceleration and deceleration and protect the rider from battery sag which may cause cut-out.  Using EUC-World statistic info - I have already "demanded" from the wheel over 3600W during the acceleration, and "gave back" over 1900W during breaking.  No issues so far.

I have also tested the high speed charging with 4,8A fast charger - wheel accepts it OK.

 

[fryman]

Could you add two more packs to the rear batteries ( 20 cells) to get 5sp. 1800wh ?

[Lukasz]

15 minutes ago, fryman said:

Could you add two more packs to the rear batteries ( 20 cells) to get 5sp. 1800wh ?

Unfortunately not, as such batteries will not fit there - Your legs are in those places. 

Also - I do not see much sense in creating heavy wheel, as for me the max needed one charge distance is around 60km (with proper safety margin left)  1440Wh is ok for that. 

KEY issue for the 4p setup is the current reserve and protection against voltage sag (winter is coming- amount of current from 3p battery will be in really dangerous levels)

[Lukasz]

Short update after 250 km. I feel much safer with this battery setup, no issues with voltage sag.  Wheel with all mods weights still below 28 kg which is quite low weight if compared to Ninebot Z10 which was about the same weight but with only 995Wh battery and without suspension. 

Wheel runs well, charges well. After balancing current goes down  to just  0,01A.  Max reached speed - 46km/h but my usual max speed is 42-43 km/h

I have tested 4.8A charger - it assures 370Wh/hour charging rate, which is enough for me - my charger offers also 8,6A current but for now I did not test it as it may be too high current for the Lenovo connector.  I have developed recently additional mods - front bumper, motor cable protector. Nylon pedals are also in progres.

[Beachboy]

Nice work, I hope you redesign the front shell ergonomically with the original frame and also to balance the weight, probably that rear shell under the shock can be added with some batteries as well..this will also redesign those pads 

[Simply_Striking]

Someone should tag kingsong on this.

[Beachboy]

@Jack King Song I cant help it, so I must tag you along..would care for this breakthrough?

[Scubadragonsan]

I think KingSong should add suspension to some of its existing models such as KS18S, KS18XL... Then one can have best of both worlds, suspension and range!

[Lukasz]

On 9/29/2020 at 8:04 PM, scubadragosan said:

I think KingSong should add suspension to some of its existing models such as KS18S, KS18XL... Then one can have best of both worlds, suspension and range!

It is not easy to fit suspension to the existing wheels. 

[Lukasz]

I have passed 400 km today on my upgraded S18, so by the end of the week I should publish 500 km YT update.

Review will include following Issues / upgrades list.  

• Suspension overhaul - ball bearings, spacers, alignment, ease of movement
• Fender plastic around the screw under shock absorber – cut down to remove collision
• Sharp edges of the pedal wedges – solved by pedal openers
• Pedal openers – needed to open pedals easy
• Pedal pins – grip is just not enough – if we think that it is off-road wheel – this is minimum (nylon pedals with stainless pins are in preparation)
• Battery holder base sharp edges – this needs to be addressed by KS – edges of the alu frame holding batteries on all 4 corners are super sharp – this is dangerous – basic remedy is to file the edges
• Motor wire protector – I have developed cover of the motor power wire which may be scraped by shoes
• Breaking and acceleration pads – offers much better overall control of the wheel
• Front bumpers – in general all suspension wheels have center of mass higher – so when not powered they have tendency to fall – my wheel is bit heavier on the front side due to additional batteries – to solve it I have designed soft rubber front bumpers which protect the wheel front in case of the small falls and also allow easy parked position
• Front lamp blinds people – for now I have no solution for that – I keep the calibration of the pedals in flat position – but it does not solve the problem in full
• Cover light sensor – In my opinion SAFETY FIRST – so in order not to bother with pressing the on key always to turn the lamp on – I just covered the light sensor with black tape – this ensures full time light ON
• Custom power  supply 4.8A is OK -  I have tested and use on my wheel (20s4p setup) fast charger – it allows 370Wh/hour of charging, but I have also used this charger on standard 20s3p wheels
• Tire/fender noises – solution - positioning through rubber inserts – it is very difficult to add washers under the black fender screws – I have found simple solution by pushing small pieces of rubber foam under the gray slider between the fender to set spacing more even
• Fender/batteries noises – those issues can be adjusted by 1-2 mm space increase by moving gray sliders more away from the motor on the axis – to make more room for internal fender
• Annoying beeps when connecting / disconnecting with EUC World - for now I just use Wheellog (version from google store) - as whellog reads less data from the KS mainboard - it just beeps twice when connecting - much less noisy

I will show those things in the YT video which will be published in a few days.

Edited October 4, 2020 by Lukasz

[Lukasz]

Work is almost done - slime added ot the tire - the last thing to add is nylon pedals which should arrive next week.

 

[Purplecycle]

On 10/8/2020 at 6:30 PM, Lukasz said:

Work is almost done - slime added ot the tire - the last thing to add is nylon pedals which should arrive next week.

 

 

Lukasz, man, your custom S18XL looks amazing! Just curious -- did you notice a big improvement in the range?

Thanks, and keep up the awesome work!

[Lukasz]

KS18XL  has now 1440Wh batery setup 20s4p which is exactly the same as Inmotion V11. 

Range is of course higher, but the term "range" is subjective -  and there is "hassle free" range - where You have no range anxiety NOR care about lower speed to increase range etc, and the various "range tests" where You limit Your speed / acceleration etc. to "reach" as far as You can, and in this situation You care about  rider weight, terrain profile, accelerations,  full charge or instead of 90% initial charge, wind, tire pressure, max speed, average speed, many other factors.  

I charge my wheels usually to the end of constant current phase (so around 90 %) after each ride (every day basically), and before the weekends to 100% including balancing phase (so to the end of the constant voltage phase where current goes down to 0,01A) 

Real world hassle-free range is 40-50 km,  (with speeds up to 45km/h with my full protection+backpack+helmet riding weight around 85 kg) - you can see my usual riding suit in the YT below. In warm weather and moderate speeds  this can increase to 60+ km  maybe more, but in my riding pattern I really seldom need higher range. In case of the longer trips I can always take with me my super light charger which is 0.5kg only and offers 4.8A / 9A charging current (although I have NOT tested 9A charging as I am afraid that it may fry the pcb) as this charger offers around 370Wh of charge per hour on low setting - this give me sufficient charging speed,  so when I stop for rest I can find the place to recharge.  

 

[Andrea]

Hi Lukasz, good job. Where did you connect the 2 batteries added electrically? on which cables did you connect them?

tnx

Andrea

[Purplecycle]

9 hours ago, Lukasz said:

KS18XL  has now 1440Wh batery setup 20s4p which is exactly the same as Inmotion V11. 

Range is of course higher, but the term "range" is subjective -  and there is "hassle free" range - where You have no range anxiety NOR care about lower speed to increase range etc, and the various "range tests" where You limit Your speed / acceleration etc. to "reach" as far as You can, and in this situation You care about  rider weight, terrain profile, accelerations,  full charge or instead of 90% initial charge, wind, tire pressure, max speed, average speed, many other factors.  

I charge my wheels usually to the end of constant current phase (so around 90 %) after each ride (every day basically), and before the weekends to 100% including balancing phase (so to the end of the constant voltage phase where current goes down to 0,01A) 

Real world hassle-free range is 40-50 km,  (with speeds up to 45km/h with my full protection+backpack+helmet riding weight around 85 kg) - you can see my usual riding suit in the YT below. In warm weather and moderate speeds  this can increase to 60+ km  maybe more, but in my riding pattern I really seldom need higher range. In case of the longer trips I can always take with me my super light charger which is 0.5kg only and offers 4.8A / 9A charging current (although I have NOT tested 9A charging as I am afraid that it may fry the pcb) as this charger offers around 370Wh of charge per hour on low setting - this give me sufficient charging speed,  so when I stop for rest I can find the place to recharge.  

 

Thanks for all this info! May I ask what fast charger model you have?

[Lukasz]

13 hours ago, Andrea said:

Hi Lukasz, good job. Where did you connect the 2 batteries added electrically? on which cables did you connect them?

tnx

Andrea

Please consult included picture from construction process - rear batteries must be connected in paralel - left rear with another left rear (all wires) and right rear with another right rear - also all the wires - be careful to ensure that battery voltage is exactly the same before attempting to connect them together and do not mismatch wires. Due to the shape of batteries I have placed them on the reverse sides - so additional rear left battery is installed on the front right, and rear right goes into front left. Cables must be managed under the mainboard cover - which must be cut a bit on the inside.  Please note the places I have connected the wires - in the upper part of the plastic channels - one by one - in separate places so it fits well in the channels - this must be soldered really well, and insulated properly. Please ensure that You have experience with soldering before this job, use the same wire thickness - AWG14 for power and AWG20 for control wires. Use XT-90I male connectors for the connection. 

[Andrea]

Hi,

thanks for the explanation, I was wondering one thing:

In this way the parallels remain 3 connected to the motherboard, or am I wrong?

Are the 2 original rear batteries put in series with each other and in parallel with the front ones?

If you add the 2 new batteries does the situation remain the same ? (always 3 parallel but more capacious)? ...

I think that this only increases the capacity of the rear parallel (2 original batteries + 2 new batteries)

but surely I'm wrong

Grazie

A.

[Lukasz]

S18 has 3 independent batteries connected to the main board - two front 84V batteries build from 20 cells, and third battery build from two back 42V batteries  build from 10 cells connected in series, connected in paralel with two front ones. Additional batteries are 10 cells each, connected in paralel to the back batteries. This whole setup works as each battery pack has its own BMS. 

[Andrea]

Ok, thanks ... so you have boosted the "third" battery bringing it to the same amperes as the front ones (the third parallel was the weaker one). In theory, you "should" have solved the problem of premature rear battery drop

 

A.

Edited October 17, 2020 by Andrea

[Lukasz]

1 hour ago, Andrea said:

Ok, thanks ... so you have boosted the "third" battery bringing it to the same amperes as the front ones (the third parallel was the weaker one). In theory, you "should" have solved the problem of premature rear battery drop

 

A.

In S18 "Third" battery is exactly the same as the two front ones - there is no "weaker" battery in the set - 3rd series of cells is just divided into 2 boxes to fit them on the back of the wheel.

Adding 4th series of batteries is not making "Third" battery stronger - it is making the 20s4p setup instead of 20s3p setup. all series are (and must be!) EQUAL