Power in Flux

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Stevo replied to the thread Electric Race Kart build.
" I suppose a congrats is in order! I'm hoping you will still be able to assist occasionally with prior customers requests ?
I was also hoping to add the BMS and bluetooth interface to my build soon... If you are not going to move forward with it, maybe I can pick up where you left off?
I'm getting close to the time of pulling the trigger on that big purchase. "

1 Day Ago

frodus replied to the thread Electric Race Kart build.
" So, Things have been kind of hectic.

I wasn't expecting to change careers into the EV world, but I should be starting work with Cascadia Motion, owned by BorgWarner, in the coming weeks. So I'm shutting down my Electro Motive Force, LLC business because of a conflict of interest. There are other places to get this combo though, likely through EVDrive.com.

A few months ago, we worked with EVDrive and built a battery pack for a major Kart manufacturer. They're modifying the chassis some, so we're waiting on that. I'll likely stick with either the 1616 or 1507 motors, and a Size 6 Sevcon. It's just taking a little longer due to the employment situation. "

2 Days Ago

Byte replied to the thread Electric Race Kart build.
" Hi Frodus,

Already for quite some months I was looking onto your website, specifically looking at the ME1507. By coincidence I found your post on this forum and saw that you're the owner of the shop.
I'm looking into going next-level by making a ultra-light electric bicycle with a bunch of power (35+ kW peak performance). I'm a Mechanical Engineer and previously build some very lightweight <15 kW electric bicycles, which are very fun to drive, but I'm looking for more I will probably contact you in a few months as I'm currently working on all the calculations and developing the frame.

I'm very curious to see an update on your build, as your last post was already from about 3 months ago.


Patrick "

2 Days Ago

Nicman clicked Likes for this post: A Proper electric motorcycle by Ted Dillard

2 Days Ago

Ted Dillard created the thread Ed Gold: Electric Motorcycles.
" So Dice chats me up on Facebook and tells me he has this guy who is loving my book, and is putting together his own photo book on electric motorcycles and is wrapping up his interview with Dice, complete with some awesome photography:

https://static.wixstatic.com/media/a...MG_1672_1.webp

Yeah, that's Dice. He got ugly.

I chat with Ed on the phone, nice guy, completely insane, but that comes with the territory. (Writing books? Photography? Traveling the world without a home taking pictures? Your call...) Anyway, since I've got not much to show for my efforts but a book on the shelf and a partially disassembled bike in the back of what used to be my shop and is now a storage container for the makerspace stuff, and he's kind of all about the photos, he elects to forego the trip to Boston and head to Florida. Can't say I blame him.

So a month or maybe 3 go by, and here's his book: https://www.edgold.co.uk/electric-mo...WEqJc2_PqE6tfM

It looks pretty sweet to me - thought I'd share it here... enjoy! "

3 Days Ago

Stevo replied to the thread A Proper electric motorcycle.
" Beautiful! "

3 Days Ago

flo replied to the thread A Proper electric motorcycle.
" Want one!!
perfect bike for my taste... guess one just need to rob a bank first to afford something like this.


Flo "

3 Days Ago

Richard230 replied to the thread A Proper electric motorcycle.
" Looks nice, but you can keep that low handlebar location and the bike lacks a top box for carrying stuff. "

3 Days Ago

Stevo replied to the thread New fluoride battery design.
" La is a rare earth used in flints for lighters and TIG welding electrode alloys. I think also used in special lighting for cinema filming.
I think I read an article about this a while ago... instead of the battery "pushing" electrons out, it "pulls" them in. Interesting concept... we'll see if it has "potential" LOL "

1 Week Ago

Richard230 created the thread New fluoride battery design.
" Honda, Caltech and NASA are trying to develop another "world-beating" battery, this one based upon fluorine. (Not everyone's favorite element on the periodic table, but they are tossing in a little copper and lanthanum, too - whatever the heck that is.) If they can get it to work, the claim is that it could have 10 times the power density of a lithium battery.

You can read a few words about it here: https://cleantechnica.com/2018/12/08...-breakthrough/ "

1 Week Ago

Ted Dillard replied to the thread Lark Streamliner EV motorcycle Project.
"
Quote Originally Posted by larkmachineco View Post
Thanks for the support. ...
It's not really a question of support. We're all trying to support the project, it's awesome. Just keep in mind that we're all coming from slightly different angles, and I was just trying to keep the point of the build in focus. "

1 Week Ago

frodus replied to the thread Lark Streamliner EV motorcycle Project.
" Those are great! They monitor and balance. I think they have temp sense inputs too.

Which linear chip is it? They have pretty nice software you can use to get them working pretty easily. "

1 Week Ago

frodus replied to the thread Sun 300-1774.
" They may not regulate the output unless hooked to a load. Can you test them with a load? "

1 Week Ago

Nicman replied to the thread Sun 300-1774.
" Hey guys!
So after sitting for close to 8 months I got the supplies out and really tore them open.
I wired up a couple of leads and they turn on, but there is no output voltage.
I'll try to see if it needs to sense a load in order to charge.

Any ideas without having to spend a ton on more leaf batteries?


Thanks!



Sent from my SM-G955U using Tapatalk "

1 Week Ago

larkmachineco replied to the thread Lark Streamliner EV motorcycle Project.
" Attachment 8161Attachment 8162

Would this make everyone feel better?
I scavenged an old project for these eval board.
I still need to make them work and build a holder for them "

1 Week Ago

frodus replied to the thread Sevcon wiring diagram.
" I'll say this from experience, that you're unlikely to create a DCF from scratch without a Dyno and some involvement from Sevcon. I have some, you'll need to test it though.

If its a race bike, I'd just use a pack-voltage rated emergency switch that goes to the DC-DC. If you hit that, everything drops. Kill switch can still disconnect the 12V relay that comes off the DC-DC to drive KSI. "

1 Week Ago

Stamen replied to the thread Sevcon wiring diagram.
" Or I was also think about a RFID switch or relay? Would something like that work/exist? Couldn't the chip in the key fob send a signal (boosted by a small coin battery) to a receiver on a relay to close the high voltage side thus enabling the DC-DC. "

1 Week Ago

Richard230 created the thread Tesla buys into new battery tech.

1 Week Ago

Stamen replied to the thread Sevcon wiring diagram.
" I was planning to create a .dcf file from scratch or start off with one for the ME1507 and modify it accordingly if I can't find access the Zero .dcf file. I think the Sevcon should be new, but I haven't powered it one yet. What other details should I share?

I know the voltage divider will fluctuate but wouldn't it still work since relays typically are designed to work within a 70%-130% range of nominal voltage (12 V here). So for me the nominal pack voltage would be (3.8V * 28cells) =106.4 V. To get 12 V to the relay at nominal voltage would require a 8.87:1 reduction ratio. So then at min pack voltage of (3.0 V * 28 cells) = 84 V the circuit would output 9.47 V and at max pack voltage of (4.1 V * 28 cells) = 114.8 V it would output 12.94 V. I was looking at the TE relay https://www.mouser.at/ProductDetail/...4le6rSrBArDQ== but I didn't see the min. and max. operating voltages on the data sheet.

Anyway I am still considering the 12 V aux battery idea. My biggest motivator to is less weight since this will be a race bike. My low voltage accessories will be minimal maybe a display, BMS, and ignition and kill switches. Do you have a recommendation for what cells would be a good fit? Also if you charge the aux battery off of the DC-DC how would you regulate the charge current/power going into the battery? via fuse? "

1 Week Ago