Search found 7322 matches

by Alan B
Apr 26, 2018 2:48 am
Forum: Battery Technology
Topic: Straight Answer on Using Lithium Power Tool Batteries
Replies: 6
Views: 209

Re: Straight Answer on Using Lithium Power Tool Batteries

We have a couple of threads exploring the EGO series of 56V yard tool packs for Ebike and other uses here on ES. There are some builds using these packs. We have a design for a 3D printed connector that is in the prototype test phase. These are 14S packs which are a good fit for 48V systems. Maximum...
by Alan B
Apr 25, 2018 7:32 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Throttle Behavior
Replies: 70
Views: 1797

Re: Throttle Behavior

This is the voltage divider setup (from above) which should provide better adjustment range. Perhaps you are already using this arrangement, but I would not call this series. The pot forms a voltage divider across the throttle output. Unfortunately when the pot is turned near the CW end the base wil...
by Alan B
Apr 25, 2018 6:45 pm
Forum: EV Business World
Topic: Tesla Model 3
Replies: 350
Views: 18385

Re: Tesla Model 3

The battery to total pack weight is about 50% on many vehicle packs, with armoring, cooling systems, bus bars, BMS equipment, fusing, wiring, etc. Even if the batteries get lighter there is a lot more weight than just cells when incorporated into the vehicle.
by Alan B
Apr 25, 2018 6:40 pm
Forum: E-Bike Non-hub Motor Drives
Topic: Throttle Behavior
Replies: 70
Views: 1797

Re: Throttle Behavior

Using the pot in series may exacerbate the temperature sensitivity, and make adjusting it very difficult and insensitive to changes. Better to use it as a voltage divider as was shown in one of the early sketches, one end of the pot to the throttle signal, one to ground, transistor fed from the cent...
by Alan B
Apr 25, 2018 6:36 pm
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

It is really nice to have a power surplus. More than nice, it is a safety feature. Power limitations on ebikes don't generally provide any margin, and the manufacturers of commercial products usually abide by those rules. So the first time you hit a big hill the bike cannot maintain even 20 mph. The...
by Alan B
Apr 25, 2018 2:19 pm
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

3-5 kW is not really adequate for safe operation at highway speeds, nor is a moped weight machine. That's motorcycle range, and they are up to 30 or even 60kW and 300-400 pounds for many reasons. Depending on where in the world you are, the rules for ebikes can be very different, and the level of en...
by Alan B
Apr 25, 2018 9:11 am
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

Choosing a 3kW DD hubmotor vs a 750W mid drive or geared hubmotor changes things in a fundamental way. This approach leads to a larger battery pack with higher current and amp hour capacity, heavier motor, and a need for tougher rims and tires. The result is a much heavier machine. While a mid drive...
by Alan B
Apr 25, 2018 8:17 am
Forum: E-Bike General Discussion
Topic: New Build with EGO 56V Home Depot Battery - Wow
Replies: 36
Views: 5236

Re: New Build with EGO 56V Home Depot Battery - Wow

Two 5.0 AH packs are about $450, plus $50 charger, so the mower's about $300. Folks should know that the power output terminals bypass the BMS on these batteries, so there's no individual cell protection or overcurrent protection, where a BMS equipped ebike pack will have both. The power tools commu...
by Alan B
Apr 25, 2018 1:44 am
Forum: E-Bike Technical
Topic: IP67-spec throttles?
Replies: 3
Views: 81

Re: IP67-spec throttles?

The Domino throttle is reportedly IP67 rated. The rating has more to do with the design of the mechanism than with whether the device is a potentiometer or a hall sensor. The pot tends to be very linear and have a wider range of output voltage, whereas magnetic devices vary considerably in their lin...
by Alan B
Apr 25, 2018 1:33 am
Forum: EV Business World
Topic: Tesla Model 3
Replies: 350
Views: 18385

Re: Tesla Model 3

Automotive batteries, including armor, cooling, bussing, etc. are not light. There is a significant cost associated with hauling around extra weight in a vehicle - hence the difference in efficiency between bicycles and electric cars. Doubling or quadrupling the amount of batteries carried around is...
by Alan B
Apr 24, 2018 9:42 pm
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

The cheapest lithium battery may have a short life, and may not be the cheapest per mile. Ebikes draw more power than the usual power tool. You want something that is cheap per mile, not necessarily the same as the cheapest in up front procurement cost. Gradients are a very important thing to consid...
by Alan B
Apr 24, 2018 8:23 pm
Forum: Battery Technology
Topic: Understanding and Using EGO Power+ Batteries
Replies: 59
Views: 1548

Re: Understanding and Using EGO Power+ Batteries

I'm not concerned about charging, that is taken care of by the charger which makes all four connections, so it has the BMS Data connection and the Temperature connection to work with. I would like to be able to get BMS information for improved discharge protection on the bike during discharge and re...
by Alan B
Apr 24, 2018 3:43 pm
Forum: Battery Technology
Topic: Understanding and Using EGO Power+ Batteries
Replies: 59
Views: 1548

Re: Understanding and Using EGO Power+ Batteries

If there is enough interest perhaps a separate thread on the Ryobi 36V batteries should be started. Most of my bikes don't run very well at that voltage. I use the Ryobi 18V packs for some tools and they are fine, but in a higher power application the cells need good cooling. From what I've seen the...
by Alan B
Apr 24, 2018 6:15 am
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

Ego has 7.5 amp hour packs for additional range. Some vendors have reduced pricing on these packs. A pair of these in parallel at 15 amp hours is a fairly long range setup. For the same power the mid drive may have the best hill climbing, the geared hubmotor second best and the direct drive the leas...
by Alan B
Apr 23, 2018 3:05 pm
Forum: Battery Technology
Topic: Bluetooth 10-15s bms review
Replies: 40
Views: 2108

Re: Bluetooth 10-15s bms review

That could provide a good value if it is a true 4 wire connection that only involves the FETs voltage drop. Ideally this would be measured on the die with separate bonding wires, this measurement made externally will include all the resistances of the leads and bond wires. The best we can do is to m...
by Alan B
Apr 23, 2018 2:53 pm
Forum: E-Bike General Discussion
Topic: Active pre-charge/inrush control
Replies: 709
Views: 58492

Re: Active pre-charge/inrush control

The dangers of trusting provided component layout libraries...
by Alan B
Apr 23, 2018 2:51 pm
Forum: E-Bike Photos & Video
Topic: My Sun Trip Bike, Back to Back Tandem Trike with Rowing Generator, Pedals, +Solar
Replies: 44
Views: 1337

Re: My Sun Trip Bike, Back to Back Tandem Trike with Rowing Generator, Pedals, +Solar

The varying load (due to the motor and driving conditions) and varying cosine angle to the sun of a solar panel array on an ebike is not consistent with the assumptions normally made when designing an MPPT controller. Of course the details depend on the algorithms chosen and the feedback parameters ...
by Alan B
Apr 23, 2018 12:07 pm
Forum: E-Bike Reviews & Testing
Topic: Sabvoton SVMC072150 controller review, variable regen *PICS*
Replies: 251
Views: 32290

Re: Sabvoton SVMC072150 controller review, variable regen *PICS*

On my setup it required both a switched signal and the variable signal. The switched signal did cut off the power (the throttle would not produce power), then the variable signal controlled the amount of braking (in addition to the settings in the controller). Here is the wiring diagram and software...
by Alan B
Apr 23, 2018 5:17 am
Forum: E-Bike General Discussion
Topic: Is REGEN, really worth it ?
Replies: 73
Views: 2073

Re: Is REGEN, really worth it ?

In the case of living on a hill and descending first, regen will not be available for this initial descent unless charging is reduced below 100%. But every other hill on the trip would be fine. As was suggested, charging to slightly lower max voltage, which is often done just for battery life, would...
by Alan B
Apr 23, 2018 12:25 am
Forum: E-Bike General Discussion
Topic: E bike Gearing Why Bother
Replies: 15
Views: 320

Re: E bike Gearing Why Bother

One gear for motoring, one for dead battery. Help it out on starts and steep hills. :)
by Alan B
Apr 23, 2018 12:13 am
Forum: E-Bike Technical
Topic: The ultimate torque arm (For <2kW and standard axles)?
Replies: 105
Views: 1748

Re: The ultimate torque arm (For <2kW and standard axles)?

I never said the wedge lock took more torque to release than something else. I said it took more torque to release it than to stay where it is. Read carefully, sorry if I wasn't clear. Actually it looks pretty clear there. This behavior has been verified with experimental results personally every ti...
by Alan B
Apr 22, 2018 3:03 pm
Forum: E-Bike Technical
Topic: The ultimate torque arm (For <2kW and standard axles)?
Replies: 105
Views: 1748

Re: The ultimate torque arm (For <2kW and standard axles)?

Wedge Locking washers like the NordLock must engage the two faces on either side to work. [...] so to release the nut takes more torque than for it to stay where it is, Nope. With or without a softer surface to bite into, they release at a lower torque than an ordinary flat washer. WbLS3rGtKDM Chal...
by Alan B
Apr 22, 2018 2:18 pm
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

My own preference is to get batteries that you can get serviced, or make your own battery. Shipping lithium batteries is difficult because they have caused planes to fall out of the sky. They can burn so fiercely that automated fire extinguishers cannot stop the blaze. Thus the rules governing their...
by Alan B
Apr 22, 2018 2:13 pm
Forum: E-Bike General Discussion
Topic: Looking for people that own E-bikes
Replies: 42
Views: 688

Re: Looking for people that own E-bikes

Not sure where you are located, good to put in at least general terms where you are into your settings so folks can use that to improve their suggestions. People differ on many things, but one thing everyone agrees on - no lead. At least on an ebike, a lithium battery is a game changer due to weight...