King Song S22/Pro, 1,776Wh Battery, 3.4KW/4KW Motor, Suspension

The S22 has undergone a number of iterative improvements/changes since the release. In order to provide Customers with the maximum amount of choice for their needs & budget, we’re now offering the S22 in 5 different variants.

1. Base: the original S22, with the 3.4KW motor, King Song sliders, & high power battery pack. Comes ready to use, out of box.
2. Slider Upgrade: on the original S22 it has a vertical sliding system, with a nylon block that runs in a metal channel; this can become progressively stiffened over time. The upgraded CNC Hou slider-kit dramatically improves this mechanism, with high-durability bearing rollers, in CNC mounting brackets. If selecting this option, the Hou CNC kit will be shipped out separately, some installation is required.
3. Slider + 4KW Pro Motor: in addition to the roller-sliders, the option includes the latest Generation 4 motor, which provides up to 30% more torque for better hill climbing. However, this comes at the expense of range, one can expect about 20% less mileage, about 50 miles as opposed to 65 miles in the original motor.
4. Install Upgrades: With this option, our in-house Technicians will install all the upgrades & test out prior to shipping. You will also have the option of choosing between a street & knobby tire.
5. Anniversary Edition S22 PRO: has all the latest upgrades preinstalled at the King Song factory. There is also the choice of street/knobby tire here too.

In celebration of King Song’s 10th year since inception, King Song produced a limited production run of their Wheels in a distinctive gold scheme for the trim, panels & the motor rims. Under-the-hood, the core components of the S22 battery pack, BMS, controller & motor are identical. One unique difference is that the ‘Classic’/Red-black S22 uses the 3rd party Hou Ningning CNC slider kit installed, while the Anniversay Edition is using the 4th generation King Song sliders (just released) that are expected to be of equivalent quality & durability to the Hou slider kit.

This lastest S22 Anniversary Edition production run, mid-August, has undergone a 7-point independent QC validation check:

1. Free motor rotation for detection of anomalous noises from the bearings/motor
2. Tire wobble, ensuring the tires are mounted correctly onto the rims, use of tire lubrication compound during installation
3. Vertical suspension movement is free, lacks unusual noises
4. Validation battery packs charge up to ~126V, with 1V tolerance
5. App connectivity, ensuring no error codes, once charged
6. Use of 12.9 grade steel bolts on the motor brackets
7. Upgraded suspension bolts linkages to the higher grade metal
   

For ‘Classic’ S22 red-and-black orders, these undergo a 10-point refit/verification operation before shippeing out to Customers. This includes:

1. Replace the original 3.4KW motor with the latest 4th gen 4,000W, steel core, for improved reliability/durability, superior bearing packaging & lubrication protection
2. Install upgraded 12.9 motor bolts to minimize the risk of stripping during tire swap operations
3. Fit tire/tube to the new motor, ensure the tire is distributed evenly around the rim
4. Install the upgraded Hou Ningning slider-kit on the motor brackets
5. Replace suspension linkage bolts/bearings with 12.9 grade steel bolts set
6. Exchange the GX16-6 charge port with the new version with embedded capacitor—to improve charger reliability
7. Update controller firmware & BMS to the latest versions
8. Test charging using both the included 5A stock charger & rapid-charger
9. Perform a short ride
10. Package everything up in the original double-walled box, create unique GoogleAlbum folder of all the work carried—this is sent to Customers prior to shipping, as proof-of-work

King Song originally selected the LG M50LT battery cell, not for any intrinsic technically sound reasons, but out of inertia from earlier S18 model. After an early preproduction demo S22 spectularly failed during evaluation, we demanded that our production of S22 use the more suitable Samsung 40T high-power cells that are rated for the massive swings in power output & regeneration that are expereniced in an application like an Electric Unicycle. 

The graphic above illustrates a core differentiation of a similar ‘high capacity’ Samsung 50E cell, to a 40T, in maintaining a higher voltage under a constant 15 Amp load—the effects of pulsed-power output in an Electric Unicycle application are even greater in the ‘burst’ capability of a cell with a significantly lower internal resistance.   

Beyond the advantage of providing more power-on-demand throughout the discharge curve, there are a number of other inherent advantages of the Samsung 40T cell, that include:

–Considerably Safer: in stress/abuse tests, the 40T battery cells can operate at a much greater range of parameters, without premature degradation of cell’s internal structure.

–Designed for Fast-charging: the 40T cell is rated for a charge rate of 6A vs 1.5-3.5A with the LG M50LT & is subject to a narrow band of temperature operation to achieve the higher rate of charge.

–Temperature Variance Range: another advantage of the 40T is that it can operated in ambientant extreme temperatures , from -4°F up to 176°F, while the M50LT cell is limited to a much more prescribed temperature range.

–Higher Operating Efficiency: with an internal resistance of 12.6mOhm vs 18.3mOhm of the M50LT, the 40T operates more efficently in higher discharge scenarios, such as high-speed runs, or sustained hill-climbing, meaning that a greater proportion of the cell’s energy is able to do useful work, rather than being converted into parastic heat. The Wh rating of a cell is not the complete picture!

–Longevity & Stability: based on available data, in like-for-like high demand applications, a high-power 40T cell will offer superior % capacity over a couple hundred cycles, than a ‘high capacity’ cell & more importantly, the risks of latent degradation, leading to thermal run-away is reduced.