Search found 840 matches

by www.recumbents.com
Apr 02 2019 3:53pm
Forum: Battery Technology
Topic: can I use five 12v power supplies in series to charge 52v battery?
Replies: 3
Views: 183

Re: can I use five 12v power supplies in series to charge 52v battery?

Short answer - yes, if they are isolated.

You will need to either babysit them until your battery is charged or figure out some way to shut them down when your battery gets to a certain voltage. I'm sure there's a circuit for that or something on ebay that will do it.

Warren
by www.recumbents.com
Feb 06 2019 12:05pm
Forum: E-Bike Build Threads / Photos & Video
Topic: High performance & durability Cannondale Semi Recumbent
Replies: 53
Views: 1894

Re: High performance & durability Cannondale Semi Recumbent

I'm not sure what Chalo just said, because I have him blocked, but I'm sure it was something like "Nya-Nya upright bikes are superior!"
by www.recumbents.com
Feb 06 2019 10:25am
Forum: E-Bike Build Threads / Photos & Video
Topic: High performance & durability Cannondale Semi Recumbent
Replies: 53
Views: 1894

Re: High performance & durability Cannondale Semi Recumbent

As you noted the biggest thing you want to avoid in a crash is contact with the frame. Don't put crash bars between your body and the pavement. It's better to use something like flat like Coroplast on the sides which will protect you from roadrash. I have rarely crashed while street riding. Most cra...
by www.recumbents.com
Feb 04 2019 12:57pm
Forum: E-Bike Build Threads / Photos & Video
Topic: High performance & durability Cannondale Semi Recumbent
Replies: 53
Views: 1894

Re: High performance & durability Cannondale Semi Recumbent

Ha. I have crashed recumbent bikes a lot, because racing. Usually you end up landing on your butt and sliding. This means you get road rash on your butt, upper thigh and usually your elbow / forearm. Not bad compared to the crash modes on upright bikes.
by www.recumbents.com
Jan 30 2019 10:09am
Forum: Battery Technology
Topic: Battery power problems
Replies: 40
Views: 1176

Re: Battery power problems

Yes, you may need to leave the battery charging overnight for it to be fully balanced, even if the green light is already on. Sometimes the batteries will cut out under a high load. This is an indication that the controller is asking for more power than the battery pack can supply. This is caused be...
by www.recumbents.com
Jan 17 2019 5:02pm
Forum: Large EV General Discussion
Topic: Lightweight AWD Sportscar
Replies: 47
Views: 4631

Re: Lightweight AWD Sportscar

Something else to think about is that most CFD systems don't take ground effects into account. I'm not a CAD expert but that's a big component of drag. It seems like most car designs leave out the aerodynamics of the underside of the vehicle. Yes, you should be able to find a windshield from another...
by www.recumbents.com
Nov 15 2018 4:14pm
Forum: E-Bike General Discussion
Topic: Sparks flying: are my battery or charger damaged? Please help
Replies: 8
Views: 455

Re: Sparks flying: are my battery or charger damaged? Please help

I'm thinking either reversed polarity or the charger is shorted. Did it cook all the metal off that side of the charger connector or is it just singed?
by www.recumbents.com
Nov 06 2018 11:28am
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

I ran the cables through the Otivia box and then discovered that they were preventing the box from being opened. Oops. Drilled more holes... After I get the lid of the box mounted I will take it on a nice long ride to test the range and then I'll be able to test the charging. I have a LiPo charger t...
by www.recumbents.com
Oct 30 2018 9:52am
Forum: E-Bike Technical
Topic: FLX ebike battery failure
Replies: 2
Views: 141

Re: FLX ebike battery failure

Unfortunately lithium batteries must be maintained. The BMS that ensures that the battery groups remain balanced can also drain the battery over time. This is likely what happened to you. If the bike is not used for a long period of time, it should be charged about monthly, or the BMS should be disc...
by www.recumbents.com
Oct 25 2018 6:27pm
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

Mounted the battery pack to the bike with the u-bolts and connected the wires. http://www.recumbents.com/wisil/e-bent/18650/commuter2018_pack.jpg Everything seems fine, cycle analyst says 47.4 V which is a bit off of the 48V it should be. http://www.recumbents.com/wisil/e-bent/18650/commuter2018.jpg...
by www.recumbents.com
Oct 25 2018 2:37pm
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

You are correct, sir. I had a 6 cell groups in series that were all 3.5V and had to bring them up to 4.0V (24V total) to match the remaining cell groups which were already 4.0V. I used a 6S LiPo charger to do that, and even though I was "bulk charging", they all charged to 4.0 volts. I connected the...
by www.recumbents.com
Oct 24 2018 8:46am
Forum: General Discussion
Topic: Motor Burn Up at 32AMAX
Replies: 24
Views: 1093

Re: Motor Burn Up at 32AMAX

LOL, Sounds like possibly you may need a bigger motor than the EZ for this job. Or pedal harder...
by www.recumbents.com
Oct 23 2018 8:37pm
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

Ok, thanks. Hooked up the old trusty LiPo charger and after figuring out how to work around the fact that the low battery voltage caused it to think it was charging 5 cell groups instead of 6, it is charging away.
by www.recumbents.com
Oct 23 2018 10:37am
Forum: Forum Rules and Features
Topic: The future of our forum - facebook versus web forums
Replies: 50
Views: 3587

Re: The future of our forum - facebook versus web forums

Thanks for performing the admin duties for the ES forums. I know it takes a large time investment to keep a site like this running. I added ckeditor to several pages on my site and it does work nicely. The main thing I see that's still a huge hole is uploading images and movies. It's so easy in FB a...
by www.recumbents.com
Oct 23 2018 10:21am
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

I installed the cut-off switch last night and am ready to connect the BMS.

Half the packs are at 4.0V, and the other half are at 3.5V. Do I need to equalize them before connecting the BMS, or can the BMS handle the cell groups with a 0.5 volt differential? It's so close!

Warren
by www.recumbents.com
Oct 21 2018 11:39am
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

Here's the pack assembly in the lower half of the Otivia box, with the wiring cleaned up and connectors added. I needed to order a new cutoff switch as the bolt was corroded onto the old one and I couldn't get it to come off. Also the pack is about 1/2" too high for the lid to close properly. Arg. O...
by www.recumbents.com
Oct 19 2018 2:07pm
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

Here's the battery pack in the polycarbonate box, with the BMS and CC HV160 controller mounted. The polycarbonate box is mounted to a plywood spacer which fits inside the Otivia hardshell bike box. The plywood is bolted directly to the bike rack. There's still space for commuter stuff like shoes and...
by www.recumbents.com
Oct 19 2018 9:10am
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

Here's the bms. The provided schematic was a bit lacking in detail so I labeled the board myself.

Image

Build is proceeding slowly. I now have the battery box figured out and mostly built. Hopefully it will come together quickly now.
by www.recumbents.com
Oct 03 2018 3:34pm
Forum: Battery Technology
Topic: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS
Replies: 28
Views: 1854

Re: 20AH 48V pack using Samsung 25R + Agniusm modules + Generic BMS

The BMS finally arrived a couple weeks ago and now I am starting to work on the pack again. At this speed it will be done by the time the snow flies. :roll: I'm removing all the cells from the packs and add a thin layer of dielectric to the ends of the cells to eliminate the possibility of battery t...
by www.recumbents.com
Sep 28 2018 2:15pm
Forum: Stand-up E-scooters and E-skateboards
Topic: Front steering ratio versus rear affecting speed wobbles
Replies: 4
Views: 256

Re: Front steering ratio versus rear affecting speed wobbles

I see a lot of good info if you google "skateboard steering geometry".
by www.recumbents.com
Sep 24 2018 12:32pm
Forum: General Discussion
Topic: Changes in the Endless Sphere Community
Replies: 16
Views: 1240

Re: Changes in the Endless Sphere Community

The changes I have seen are that as e-bikes became more mainstream there are fewer cool projects and more people asking how to fix things or how to upgrade. Other than that, I think the e-skateboard scene has really taken off. Speaking of that, I was in Ft. Lauderdale, FL recently and saw several pe...
by www.recumbents.com
Aug 21 2018 10:52am
Forum: Items for Sale - New
Topic: N.E.S.E. the no solder module
Replies: 277
Views: 29788

Re: N.E.S.E. the no solder module

My Samsung 25R cells fit tight too. Also the covers were very tight, I had to squeeze the pack to get them on. It's a good thing that they are tight as the mechanical connection is better that way. I was able to get all cells but the end ones out without issue. If you pry on each end of the battery ...