Power in Flux

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

1 Day Ago

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

2 Days Ago

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

3 Days Ago

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

4 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! "

4 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. "

4 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! "

4 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. "

4 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. "

4 Days Ago

kyleg780 created the thread Making the best of Midwestern summers.
" Hey guys,

I have been a member (not very active) of Endless Sphere for almost 5 years now, but I've found that there are not nearly as many motorcycle conversions over there, for obvious reasons. So here I am.

I have built an electric bike and a longboard, but motorcycles seem a bit more serious, so I decided I'd look for advice here.
I just picked up some Lithium Titanate batteries off Ebay: https://ebay.to/2LelWVl , which I chose for their high discharge and charge rates, but mainly because they were cheaper than an 18650 pack of equivalent power, while still having enough range. They also come as two pre-made EV packs (Honda Fit I think), so I don't have to do much with them. The two packs in parallel total for a little over 2kWh, which at a pessimistic 150wh/mi would give me a bit over 13mi of range.
For a motor I'm going with a QS 273, for both simplicity and better regen than a mid-drive (I think). https://bit.ly/2RUbk0q
As for a controller, I am waiting on Mobipus to figure out their stuff. When they do, they could be OEM level quality at a fraction of the price and with more features. Here's a thread from endless sphere: https://endless-sphere.com/forums/vi...6225&start=100
I am still looking for a donor bike. Hopefully a <250cc sport bike, but I might end up settling for a classic motorcycle like a Honda CB, which are far easier to find for under 800USD.

That's about it. Please let me know if you have any suggestions or if any of the above ideas won't work.

-Kyle "

4 Days Ago

jhaggerty created the thread WTB ME1003 or similar (ME709).
" Hi All,

I'm working on converting a suzuki RF600 for a senior design project in college and am in need of a motor. Our budget is fairly slim but we've been lucky to run into deals and generous people so far, so if any of you have an ME1003 or ME709 that needs a new home for a good price please send me a message!

Thanks,

-J "

4 Days Ago

jhaggerty replied to the thread Finding High Power Lithium-ion battery Chargers.
" 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. "

5 Days Ago

frodus replied to the thread Finding High Power Lithium-ion battery Chargers.
" I don't know, you're the one who brought up building something with Elcon flatpacs You'll have to see how they communicate. I've only worked with flatpacks you set via potentiometer. I know nothing about the ones you're considering.

Brandon's charger has CAN, but also has a Canbus control board for it so you can adjust voltage and current setpoints. It's also 3.3kW. "

5 Days Ago

Zotto replied to the thread Finding High Power Lithium-ion battery Chargers.
"
Quote Originally Posted by frodus View Post
Set the charger output voltages that of the final voltage you want. The power supply voltage will be that of the battery, so it'll start out low, and since there's a voltage difference between what the charger is set to, and the battery voltage, current will flow. Basically, the chargers will put out current at CC until they reach the voltage setpoint, and then switch to CV, and the current will naturally taper towards 0A.

There's the $500 supercharger Brandon is doing, might talk to him:
https://www.indiegogo.com/projects/d...uction/x/16882

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. "

5 Days Ago

frodus replied to the thread Finding High Power Lithium-ion battery Chargers.
"
Quote Originally Posted by jhaggerty View Post
Im working with Zotto on this project. I was looking at building out a charger using Elteck flat packs or similar, but where were 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.
Set the charger output voltages that of the final voltage you want. The power supply voltage will be that of the battery, so it'll start out low, and since there's a voltage difference between what the charger is set to, and the battery voltage, current will flow. Basically, the chargers will put out current at CC until they reach the voltage setpoint, and then switch to CV, and the current will naturally taper towards 0A.

There's the $500 supercharger Brandon is doing, might talk to him:
https://www.indiegogo.com/projects/d...uction/x/16882 "

5 Days Ago

jhaggerty replied to the thread Finding High Power Lithium-ion battery Chargers.
" 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. "

5 Days Ago

Zotto replied to the thread Finding High Power Lithium-ion battery Chargers.
" Probably in the $500 range for charging solution. "

5 Days Ago

frodus replied to the thread Finding High Power Lithium-ion battery Chargers.
" Most, if not all, chargers we work with these days are CC/CV with a setpoint. for a 6-7kWh pack, a 1000W charger would take about 6-7 hours. You can double them up and do it in half. Just depends on your budget. Do you have thoughts on budget?

I can get you TCChargers if you want, just don't list them on my site. "

5 Days Ago

Zotto replied to the thread Finding High Power Lithium-ion battery Chargers.
" 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.

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. "

5 Days Ago