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Richard230 replied to the thread Lightning "Enters Production".
" After reading that article, I still don't see any evidence of an active production line. (Even their dog looks sleepy.) Things look just like it did in the photo of their production line that I saw two or three years ago. That photo was taken from the other end of that assembly room and showed four partially assembled motorcycles in line. At the time it looked to me like the "factory" was about 40 feet long and maybe 15 feet wide, to the best of my recollection. Not exactly like the Brammo factory when they were producing the Empulse. I think I would want more evidence (such as more photos of the "factory" and fewer random promotional photos taken years ago) of an actual manufacturing facility than just that one very limited photo on the Instagram link contained in the InsideEV article. It seems to me that the author of that article is jumping to a conclusion that is supported by little evidence other than that claim by Lightning and a single, intentionally limited, photo showing the front of a single partially assembled motorcycle, on something called Instagram. Or am I missing something (again)?

I would need more evidence than that before I starting shouting to the World that Lightning is finally producing motorcycles for sale to the public in more than single-digit quantities.

Attached are some photos that I took in 2014 of the Lightning display at an EV show. At least those bikes looked fully assembled. "

10 Hours Ago

Spoonman clicked Likes for this post: Open source brushless motor by Richard230

13 Hours Ago

Ted Dillard created the thread Lightning "Enters Production".
" This just annoys the b'jeesus outta me, but you know how I get.

In 2009 they claimed to be the "fastest production electric motorcycle". For all their specious "Firsts" claims, see this: http://lightningmotorcycle.com/about...ghtning-first/ With 3 actual sales in their entire history, and possibly less than ten actual bikes built, the LS-218 doesn't qualify for any definition of "production" in use in the English language. Above and beyond that, the bike that set the records resembles the actual LS-218 only remotely.

Now InsideEVs is reporting they're "entering production"? So is this an admission that they weren't in production before? Or is it simply scraping the bottom of the "what are we gonna write about this week?" barrel?

The story really pisses me off when they go on to say "If anything, Lightning has been flipping the script on the typical startup, which is: 1) Market heavily, 2) Make huge claims 3) Deliver little proof." I don't see any flipping of any scripts here.

Don't get me wrong. I love the bike, I love the looks. I'd love nothing more than to see the bikes being built and sold. I'd also love, however, to see some honest communication and coverage. "

14 Hours Ago

Richard230 created the thread Open source brushless motor.
" This might be of interest to someone that likes to build electric motors. (That would be someone other than me. )

http://www.masinaelectrica.com/open-...-construction/ "

1 Day Ago

jhaggerty replied to the thread WTB ME1003 or similar (ME709).
" Hey all, I'm still looking. FYI i'm running a ~100V pack otherwise I would have taken Stevo up on his offer. "

1 Day Ago

Zotto clicked Likes for this post: Finding High Power Lithium-ion battery Chargers by jhaggerty

1 Day Ago

Zotto clicked Likes for this post: Finding High Power Lithium-ion battery Chargers by jhaggerty

1 Day Ago

Zotto replied to the thread Finding High Power Lithium-ion battery Chargers.
" Wow, that makes a ton of sense! Thanks so much! "

1 Day Ago

Richard230 replied to the thread The latest electric motorcycles and scooters.
" Here is another new low-power (3KW) city motorcycle from the startup Fly Free Smart Motorcycles. Just like their Scrambler model, their cafe racer is nice looking. But why does is look fast, yet it has a top speed and maximum range only usable in city riding? https://electricmotorcycles.news/fly...smart-classic/

Is it really that difficult to design and manufacture a nice looking electric motorcycle that is capable of freeway speeds and has a range of over 100 miles? Zero could use some competition. "

1 Day Ago

Spoonman replied to the thread Finding High Power Lithium-ion battery Chargers.
"
Quote Originally Posted by Zotto View Post
Hmm can you explain how the DC power supply clamped to Vmax would work in that case, I thought the supply voltage was supposed to float to whatever the current source from the power supply set it to, then eventually when the pack reaches ~4.2V/cell the constant voltage took over.
Apologies for the slow reply - I see Frodus has provided a few answers already so what follows may amount to some repetition but howevenever here we go.

CC-CV as you know means Constant Current Constant Voltage and refers to the preferred approach to charging Li-chem batteries. Put very simply, the CC amounts to the max current of the appropriate DC supply for charging the pack and is a factor of either the charge uptake constraints of the cells in use, or of the power capacity of your DC supply. The CV then (again keeping things simple) amounts to the max voltage of the DC supply.

So now, lets examine the arbitrary case of a 10s arrangement of Leaf modules. 10s give you a VMax of 84V across the pack and 20 cells in series to monitor.
Those modules have a nominal charge capacity of 60Ah and lets assume a max charge acceptance of ~5C meaning that you can charge them at up to 300A.
So, at its most basic, your Charger will have a max current of 300A and a max voltage of 84V. Peak power delivery will likely occur at that 84V threshold where the cycles changes from CC-CV meaning that that power supply would be rated at somewhere in the region of 25kW (again we're just being arbitrary about things here).

Now once the DC power supply conforms to that charge current, and that maximum voltage, then that's all that's required of it. The whole CC-CV bit actually takes care of itself and here's why:
If you're engaged in this sort of a project in a school setting then I'm going to expect that you're familiar with Ohm's law - yes? ...and you should also certainly be familiar with Kirchhoff's laws and the idea of an 'equivalent circuit' as well .. yes?
Well, in this case you have two components in play - you have the battery, and the charger. Each has its own resistance (in this instance most commonly referred to as its 'internal' resistance) and assuming ideal wires linking the two together then the only current limiting factors in the circuit are these resistances - agreed?

So lets assume a circuit where the positive terminal of the DC power source is connected to the positive terminal of the battery with a switch in between, and the respective negative terminals likewise.
Attachment 8120

If we were to assume zero resistance at any point in the circuit (internal resistances included) then there would be infinite current flow arising on account of any difference in voltage between the battery and the power source - agreed?
[I=V/R -> if R == 0 then I == inf]

So now we introduce the resistances.
Attachment 8121

So now R!=0 meaning that there is a characteristic limit to the current which will flow in the circuit for any given voltage differential between the two voltage sources. In this initial scheme lets assume were in the CC stage of the charge. Accordingly the effective resistance of R(psu) >> R(batt) as the current limit of the supply is in play. As a result if we close the switch and measure the voltage at the point between the two resistances with reference to the common line, what we will find is that the voltage at that point will be equal to the V(batt) + I*R(batt) regardless of what the design voltage of the PSU is. This happens specifically because the current limit is being enforced, and the current limit is being enforced because the battery is able to draw far more current than the PSU can produce.

This will remain the case until such time as the sum of V(batt) + I*R(batt) becomes equal to V(psu) - I*R(psu). At this point there is no longer sufficient voltage difference between the source and the battery for the full current to be pushed through the circuit and hence the current limiting condition will cease to be in effect and the CV portion of the charge begins. From here on out, as the voltage of the battery continues to climb, the portion of the total voltage difference between the battery and the supply which is dropped across any given resistance is reduced, and so the current flowing also reduces - hence the system is self limiting and requires no further governance. Which is to say that CC-CV is far less of a strategy, and far more of a direct consequence of the application of a power source which has a fixed maximum voltage and current. (Which isn't to say that the CC-CV charging strategy isn't in fact 'a strategy', it certainly is. It's merely a happy coincidence that it's also very easily implemented)

Quote Originally Posted by Zotto View Post
I am designing my own BMS actually! This is for our senior design at school, the BMS design is nearly done, and should hopefully work, but I well be doing a ton of testing to ensure that it does.
How are you defining BMS (ie: monitoring system or management system [lets try and avoid the third association. :P])


Quote Originally Posted by jhaggerty View Post
I’m working with Zotto on this project. I was looking at building out a charger using Elteck flat packs or similar, but where we’re running into confusion is the constant current distinction. Is it appropriate to use a power supply like the flat packs stacked in series and set to a voltage set point to charge for the CC portion of the charge cycle? We were getting confused on whether the voltage of the charger is supposed to match with the cell voltage during the CC charge cycle.
Think the above covers that.

Quote Originally Posted by Zotto View Post
Hmm, that does make sense! When you say "set" these values, is it done manually, or over an I2C or CANbus? I am assuming its different for each charger solution, but I have no interest in implementing a CANbus for our electrical system, so I was hoping I could find a manual or I2C driven charger.
Again, I think the above covers that.
Comms need only be required for charge interruption or initiation, and even then that can be achieved with relays.
They also permit more advance controls such as charge current derating based on pack temperature etc.. nothing you need to worry about in the school project landscape. "

1 Day Ago

Chambers created the thread Noob saying hi.
" Hi all, New to the forum just saying thanks for the add. "

3 Days Ago

Ted Dillard clicked Likes for this post: Elmoto v2.0 Data sheet by kyleg780

4 Days Ago

kyleg780 replied to the thread Elmoto v2.0 Data sheet.
" Awesome, thanks "

5 Days Ago

kyleg780 replied to the thread Elmoto v2.0 Data sheet.
" Does anyone still have a copy of the spreadsheet floating around? "

6 Days Ago

kyleg780 replied to the thread Making the best of Midwestern summers.
" I will definitely start a build thread. I might also start calling up local scrap yards to see if they have any rollers or frames, as swingarms and wheels for some motorcycles seem readily available on ebay. Unfortunately I don't have enough to buy everything at once, but the bike is next on the list so I can start planning.
Thanks for the welcome! "

6 Days Ago

jhaggerty replied to the thread Finding High Power Lithium-ion battery Chargers.
" Yeah that was a slip up, we've been referring to them as modules when talking charging/bms/ pack voltage etc. amongst ourselves.

Here's the link, though I bought all that were available. https://www.ebay.com/itm/362501044768 They're not the HE or S version, hence the silver front plate and low price. I haven't found a great deal of info on these ones in particular, but have found a specs sheet that talks efficiency other specs. I'm hoping they are programmable using the same communications that Remmie has used. "

6 Days Ago

Stevo replied to the thread Making the best of Midwestern summers.
" Welcome!
Since you are starting your build around the battery pack and motor instead of around the donor bike like alot of us here, your doing things a little different already! I guess keep an eye on your local craigslist ads to see what kind of donors comes your way. Older bikes with steel frames are easier to weld and work with than the newer Al ones is something to consider, but the newer bikes have better suspensions and brakes. Try to find something with a wider frame engine cradle, like an inline 4 cylinder bike... those will give you the most room for your batteries.
Good luck finding a great donor and start a build thread posting with lots of pics when you get the project started. Cheers! "

6 Days Ago

Stevo replied to the thread WTB ME1003 or similar (ME709).
" Do you need a controller too? I have Noah's AXE7245 and a Thunderstruck-ev competition ME1003 as a pair. I wont separate the two!
I can throw in a contactor and main fuse to sweeten the deal if you need other parts as well. I also have a Vicor dc-dc for the 15volt side of things. Let me know. "

6 Days Ago

frodus replied to the thread Finding High Power Lithium-ion battery Chargers.
"
Quote Originally Posted by jhaggerty View Post
Hoping I didn't make some sort of mistake in reading the listing, but after a quick ebay skim I saw 4 eltek flatpack2 1800W units for $30 each here in the states... almost 4x less than any other units I've seen since hearing about using these. Ended up springing for all 4 with the intent of a 2s2p ~7kW charger or 2 separate 3.6kW chargers that might be paired in parallel. These will be mated to 12 or 14 nissan leaf cells.

Thanks for your explanation @Frodus- it made it much clearer how they should work.
Do you have a link for the Flatpack 1800W?

I'd suggest that you consider using the terminology "Leaf Modules" or "Leaf Batteries". Each of those modules has 4 cells in there as a 2s2p setup. 14s is only ~51.8V Nominal. But when you say 14 modules of 2s2p, that brings it up to 28s in reality, and a Nominal voltage of 103.6V. "

6 Days Ago