[RoninKW]

Hello,

I recently decided I want to start on a new project and EV conversion sparked my interest. It is something new to me that would allow me to learn while tinkering. I have only minimal experience with motors etc building a RV car from Technic Legos, random parts and an Arduino. So that's the main area I am need help in.

I tried laying out what my goals for the project would be:

I weight about 170 lbs and want to convert a motorcycle frame that would be >190 lbs and <300 lb. I didn’t calculate it but I think the EV parts may come close to 200 lbs. My hope is that I can get to operate up to speed 80mph max but 70 is good enough if that is a stretch. I understand that some of that is reliant on gearing ratios.

This conversion would serve as my commuter vehicle as long as there is no snow, ice or heavy rain. My route is mainly straight line with some very minor hills. It is 20 miles on a 55mph backroad with a chance to run a few miles (~5) on a 65mph highway. So I am trying to spec the build to give a minimum range of 60 miles but I would settle on 55 mi.

I read through a few forums and articles and also watched some YouTube videos to determine the parts I would need and how to roughly calculate possible range and speed.. however, since I'm brand new I'm not confident that I am even close. So, an experienced voice would be appreciated.

These are the part lists that I came up with. One is a configured kit and two are bare parts list. There is also a list for a DIY battery pack and "extra" items like a BMS etc... This is just based on the searching I have done over the past 48 hours. So, I don't know of better options that might better suit my goal, reduce cost or make the project more likely to succeed.

If I understand correctly to get the 55 mi range around 70mph I could use 30 3.2v cells rated 60ah (3C) giving 96v. I was using this calculation:

80v * 60ah battery = 4.8 kWh (25 cells)
Assuming 100 wh/mile
4,800/100 = 48 mi

So

96v * 60ah battery = 5.760 kWh (30 cells)
Assuming 100 wh/mile
5.760/100 = 57.6 mi

I don’t need the full power to also be used on speed though. I don’t need to be able to reach 80 if that means having more range. I am getting that how those cells are arranged will also impact the power output I just don’t have an understanding of how to calculate that yet. Maybe this could be replicated with the small bare Samsung cells?

Any advice/pointers/suggestions would be greatly appreciated. Looking at the prices it may be some time before I get to start the project.

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List 1 (Specs based on BenjaminNelson build)
Motor
Motenergy ME1003 (ME1909) PMDC Motor 12-72VDC 11.5kW Cont. 20kW Pk.
$680.00

Controller
Regen, Waterproofed
KDZ - Brushed DC Series/PM Motor Controller (12V-120V) (200A-550A) - Kelly Controls 72v 550A
$358.00
or
Same controller, Kill switch, Fuse, Contactor and throttle.
$546.00

Contactor 600a 72v
KZJ 600A Main Contactor (72V) - Kelly Controls
$99.00

Fuse?
CNL 500A Fuse - Kelly Controls
$3

Missing Cables, Connectors, Kill Switch, Key Switch, Fuse , circuit breaker (for maintenance), Software, Manuals
$1,140 or $1,226

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Kit (Preprogrammed)

Motor, Controller, Contactor, Throttle, Rocker Switch Kill Switch, Keyed Switch, Regen
ME1507 / Sevcon Gen4 72-96V 550A Motor Drive System - - PMAC IPM Turnkey Systems - Brushless PMAC Turnkey Systems - DRIVE SYSTEMS
M1507/Sevcon gen4 72-96v 550a Kit
$3,650.00

Fuse?
CNL 500A Fuse - Kelly Controls
$3

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List 2 (Specs based on BenjaminNelson with increased cost)

Motor
ME1507 (ME1905) Brushless 14.5kW Cont. 44kW Pk. IPM Motor 48-100V - - Brushless IPM Motors - MOTORS - EV PARTS
$1,029.00

Controller
KLS-8080I/IPS - High Power Opto-Isolated Sinusoidal Wave Brushless Motor Controller (72V-144V) (200A-700A) - Kelly Controls 96v. 600a. Sine/cosine speed sensor
$799.00

Contactor 600a 72v
KZJ 600A Main Contactor (72V) - Kelly Controls
$99.00

CNL 500A Fuse - Kelly Controls

Fuse?
CNL 500A Fuse - Kelly Controls
$3

Total $1,900

Missing Cables, Connectors, Kill Switch, Key Switch, Software, circuit breaker (for maintence), Manuals (Diff $1,853)

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Battery Pack

Affordable Electric Vehicle Batteries & Components from Electric Car Parts Company
60Ah 3.2v with 3C
80v = 25 cells
96v = 30 cells

5.4L * 1.6W * 8.3H in
137 * 40 * 211 mm
3.7 Lbs. / 1.7 Kg

30 cells * $75 = $2,250 - $1853 diff with unprogrammed system = 397
30 cells * 3.7 kg = 111 lb

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Total top: ~$2250 + $1,900 = $4,150
Total top: ~$2250 + $1,226 = $3,476

Minus BMS, Gauge, Converter, Shunt, Charger
So + $439.44 + $79 + $?110? (Throttle), Charger $209 = $837.44

Total Minus Gauge + Shunt + Software + Manuals: $4,150 + $837.44 = $7,987.44
Total Minus Gauge + Shunt + Software + Manuals: $3,476 + $837.44 = $4,313.44

Plus max $1,500 for Doner frame include LED headlight, small 12v battery (?capacity ah?), and LED brake light.
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"Misc parts"

BMS
4.37US $ 9% OFF|smart ant bms circuit board 16S 48V 300A 400A 500A bms with Bluetooth UART RS485 CAN for lithium ion battery pack With Fan|Battery Accessories| - AliExpress 500a (439.44 - UART485CANFAN)

DC/DC Converter
KL DC/DC Converter (40V-200V Input) (13.5V Output) 30A - Kelly Controls in 75v - 130v to 13.5v
$79

Throttle
Domino 0-5k Ohm Twist-Grip Throttle
$110


Charger (off-board, top to speed charges)
KP-E(600W) 72V 24S LiFePO4 6A Charger [KP-E24SLF] - $90.00 : EV Assemble, LiFePO4, Electric Bike Conversion Kit, EV Charger, BMS, EV Components, EV Parts, All for EV!
KP-E(600W) 72V 24S LiFePO4 6A Charger
$90

https://www.aliexpress.com/item/32855550592.html?spm=a2g0s.9042311.0.0.27424c4dIpJJ38
8am charge (116.8V 8A charger for 32S LiFePO4 battery pack )
$137.75

http://www.evassemble.com/index.php?main_page=product_info&cPath=3&products_id=225
KP-C(1200W) 72V 24S LiFePO4 12A Charger
$209

Gauge
Cycle Analyst V2.3 (High Current)
Pricing?
Source?

Shunt ?
Spec?
Pricing?

Inertia Switch?
Spec?
Pricing?
Source?

Safety Interlock (Shutoff if charging)?
Spec?
Pricing?
Source?


Low Voltage cutoff?
Spec?
Pricing?
Source?

Precharge Capacitor?
Spec?
Pricing?
Source?

Circuit breaker (for maintenance)
Spec?
Pricing?
Source?

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[RoninKW]

Found the EVdesigner spreadsheet so that is helping with calculating a real battery pack. Google Sheets EV Calculator

 

[cricketo]

I have a 2014 Zero DS with 11.4kWh battery which I took on the same ~48 mile trip multiple times a year for several years in a row. When the bike was new, typically I got to the destination with about 30% remaining, and back (after a recharge) with 40% remaining. The difference between the two was wind - the route was towards the coast, with more head wind than in the opposite direction. Speed was 55-60MPH about 2/3 of the way. Bottom line, I think you will come significantly short on your expected numbers, and may need to at least double your battery size. Additionally I am skeptical you will be able to reach those speeds (especially if you keep the battery that small). I think you should look at Zero models for inspiration on what components to use in order to achieve your target specs.