Search found 12 matches

by ndavidow
Feb 03 2018 9:38pm
Forum: Endless-Sphere Wiki
Topic: How to Register?
Replies: 1
Views: 1258

How to Register?

Wiki registration appears to be locked; is it? Can anyone hook me up with an account? Thank you.
by ndavidow
Mar 27 2017 9:27am
Forum: Battery Technology
Topic: 36v vs 48v batteries
Replies: 12
Views: 1007

Re: 36v vs 48v batteries

To get the energy the battery can hold, multiply the charge (number of amp hours) times the voltage (this gives watt hours). A 36V battery will store 25% less energy than the same Ah 48V battery, because it has 25% less voltage. So, the 36V battery will theoretically have 25% less range, or three qu...
by ndavidow
Mar 27 2017 12:11am
Forum: Motor Technology
Topic: BLDC Motor Integration w/ Motor Controllers
Replies: 5
Views: 751

Re: BLDC Motors Integration w/ Motor Controllers

Is it possible your new controller is not three phase? Will it work sensorless? Have you tried swapping the phase wires around in different combos? More info on your Anaheim controller would be helpful.
by ndavidow
Mar 26 2017 10:51pm
Forum: Motor Technology
Topic: Charging ebike without chargers?
Replies: 10
Views: 718

Re: Charging ebike without chargers?

If your bike has regen this would be easy. Just have to lift the rear wheel off the ground.

You would need to watch your voltage though so you don't overcharge. Or the whole fire dept will get some exercise too.
by ndavidow
Mar 26 2017 9:05pm
Forum: E-Bike General Discussion
Topic: Lipos a good option for high performance small pack?
Replies: 73
Views: 3689

Re: Lipos a good option for high performance small pack?

The 18650s out now are higher energy density than any lipo I'm aware of but only if you have low power requirements on a small pack or a very big pack to fulfill heavy power requirements. For a 18650 pack w/ 20 amp continuous discharge rating to deliver the requirements for a pack like MadRhino men...
by ndavidow
Mar 25 2017 4:27pm
Forum: E-Bike General Discussion
Topic: Lipos a good option for high performance small pack?
Replies: 73
Views: 3689

Re: Lipos a good option for high performance small pack?

Another downside I dunno if anyone has mentioned is weight. These super-high discharge packs look significantly heavier per Ah than good high capacity 18650. They trade off electrolyte for more anode and cathode, which makes them heavier and more volatile per Ah. Good for short RC plane flights, whe...
by ndavidow
Mar 25 2017 2:07pm
Forum: E-Bike Build Threads / Photos & Video
Topic: Redefining the "SLA" ebike
Replies: 8
Views: 1516

Re: Redefining the "SLA" ebike

Nice to see another V2100! I picked one up on craigslist several weeks ago for my first (budget) build. Still waiting on my motor and batteries, but I swapped out the front brake caliper and rotor today (stock one was garbage and already broken), what a world of difference. I've never worked on bike...
by ndavidow
Mar 22 2017 1:07pm
Forum: Battery Technology
Topic: Without BMS
Replies: 25
Views: 1711

Re: Without BMS

Seems kind of silly to not have a circuit monitoring each parallel group of cells, if you want to prolong the life of your pack. You really, really don't want any individual groups going above 4.2V, under 2.5V, or significantly over temperature (120F/50C). Judging the voltage of the whole pack can e...
by ndavidow
Mar 20 2017 2:14am
Forum: E-Vehicles General Discussion
Topic: Boston's new nightmare inducing robot
Replies: 6
Views: 857

Re: Boston's new nightmare inducing robot

The US military/DARPA has been one of the major funding sources for Boston Dynamics. IIRC their original dog thing is/was available to special forces as an alternative to pack mules, but was often not used because they were powered by loud gas engines which would compromise stealth in operations. Mo...
by ndavidow
Mar 19 2017 9:03pm
Forum: Items for Sale - New
Topic: Bulk Pricing: Sanyo NCR1865GA $4.50 USD each
Replies: 4
Views: 937

Re: Bulk Pricing: Sanyo NCR1865GA $4.50 USD each

Seems like a decent price, unfortunately Tumich is not offering the bare cells at the moment. Almost every other place I can find wants $6 USD at least per cell, after shipping. This company is based out of and ships from Hong Kong. Anybody ever order from them?
by ndavidow
Feb 27 2017 5:22pm
Forum: E-Bike General Discussion
Topic: Custom genesis v2100 torque arm
Replies: 7
Views: 865

Re: Custom genesis v2100 torque arm

How's this working for you? I've got the same frame, going to attempt a similar one.
by ndavidow
Feb 27 2017 12:47pm
Forum: E-Vehicles General Discussion
Topic: induction charging and balancing?
Replies: 4
Views: 588

Re: induction charging and balancing?

The problem with these systems is they are somewhat inefficient. Making it wireless causes some power loss. If you can plug it in, that's generally the way to go, from an efficiency standpoint.