Wheazel
10 kW
Looks good, does the poron work well? Done any shakedown tests?
18650 battery Kit development and discussion[testing done]
- Thread starter agniusm
- Start date
agniusm
1 MW
I left my first prototype for half a year probably at 80-90 compression and then did shake down discharge. Cells got warm, i was doing ~80A. I will do more tests on this one. Fitted NTS10k and pressure sensor and i have arduino logger to store raw data. I just need to finish working out how to automate conversion raw data -> degrees centigrade in excel as well as pressure. And do some charts so i could share my data on performance.
Hummina Shadeeba
1 MW
https://www.rogerscorp.com/ems/poron/industrial/index.aspx
wonder how it will do with heat as it says it shouldn't be used/stored over 80f.
I dont see it in your pics. which of the many varieties did you use?
maybe it's back in the thread but are you going to somehow protect the copper from oxidization or use conductive paste?
wonder how it will do with heat as it says it shouldn't be used/stored over 80f.
I dont see it in your pics. which of the many varieties did you use?
maybe it's back in the thread but are you going to somehow protect the copper from oxidization or use conductive paste?
agniusm
1 MW
Copper will be nickel plated. I don't need to spend on this at the moment on testing samples. Poron is 4407 i think, i have to look it up but its soft.
I have measured the compression force at ~50% poron compression and it is 700ohm's on FSR sensor which translates to 5N or .5kgf
I have measured the compression force at ~50% poron compression and it is 700ohm's on FSR sensor which translates to 5N or .5kgf
agniusm
1 MW
Hummina Shadeeba said:
This is wrong data. The one i am using states :
recommended constant use, max 90C (194F)
recommended intermittent use, max 121C (250F)
I love your design, but in my application I would need 28s20p pack.
Or if there would be some air cooling then 28s16p would also do
I assume it can be split into two smaller 14s16p pack or four 7s16p packs.
But 16p still wount fit to the printer
Or if there would be some air cooling then 28s16p would also do
I assume it can be split into two smaller 14s16p pack or four 7s16p packs.
But 16p still wount fit to the printer
agniusm
1 MW
Guys, please read up. Its not gonna be sold printed. Printing is for prototyping only. Also only 3p and 6p will be available
e-beach
10 MW
I say it is beautiful work. For those who don't have a 3D printer in their workshop, I suggest getting a free cad program and design your own battery pack to see how much work goes into it. Then think about the time (in hours) it takes to 3D print something. Then research the cost of getting production plastic molds and machined parts made. Then add the cost and production and then marking. We are talking thousand so of $$$$$'s by the time it is all done
Now think about configuring 12s and 13s and14s and so forth and multiply the costs. It all adds up to an huge amount of time and a large amount of money.
My hat is off to agniusm for taking this project so far as it is!!!
Now think about configuring 12s and 13s and14s and so forth and multiply the costs. It all adds up to an huge amount of time and a large amount of money.
My hat is off to agniusm for taking this project so far as it is!!!
tomjasz
1 GW
e-beach said:My hat is off to agniusm for taking this project so far as it is!!!
I'm excited to have whatever comes from out. I have several motors that can utilize the existing design. Very exciting to see this continueing. All good things take time.
agniusm
1 MW
I have done a full discharge test. Done a video also. I will dump it here without editing or narrating it. I have amount of sensor RAW data i need to calculate into meaningful values and do some charts to see what and how changes. I had connected oscilloscope to one S connection to see if and how voltage changes or if it changes. I am complete noob in using it so hopefully there will be some valuable info there.
This is a first video of capturing my shaker movement phase. It shows something like 300RPM so i guess the PORON gasket would compress at a rate of 150 time per minute or 2.5 times a second.
Let me know if i am wrong. We need to know the value when battery moves towards one end of the axis cause the other end would be PORON deflection.
P.S. Its nowhere near as fast loaded"
[youtube]NPsxcqrdWQ0[/youtube]
This is overview of the stuff im using:
[youtube]EN9hQLgSBek[/youtube]
Testing:
[youtube]edW-Y3fgIeM [/youtube]
Battery case temperature after test:
[youtube]WOFw_gMRQ7o[/youtube]
This is a first video of capturing my shaker movement phase. It shows something like 300RPM so i guess the PORON gasket would compress at a rate of 150 time per minute or 2.5 times a second.
Let me know if i am wrong. We need to know the value when battery moves towards one end of the axis cause the other end would be PORON deflection.
P.S. Its nowhere near as fast loaded"
[youtube]NPsxcqrdWQ0[/youtube]
This is overview of the stuff im using:
[youtube]EN9hQLgSBek[/youtube]
Testing:
[youtube]edW-Y3fgIeM [/youtube]
Battery case temperature after test:
[youtube]WOFw_gMRQ7o[/youtube]
agniusm
1 MW
I have checked my sensor data and compression sensor had no change which was weird. So i went checking and discovered that compression force at 700ohms is not 1/2 kilogram but more like 5 kilogram per cell. That could translate into sufficient force to keep it in place without even sightly mooving which is good.
I see the temperature raise but need to calculate to centigrade from ADC.
Also I am recording my values at 100ms intervals and shaking is 2.5 cycles a second so I might not catch the data at extremes but I should get some in that test time.
I see the temperature raise but need to calculate to centigrade from ADC.
Also I am recording my values at 100ms intervals and shaking is 2.5 cycles a second so I might not catch the data at extremes but I should get some in that test time.
Attachments
agniusm
1 MW
While testing my USB cable got disconnected due to whole dancing thing and some data was lost. I still recorded data for most of the discharge cycle. If someone is interested in raw ADC numbers I have attached CSV.
1 column - time, ms
2 column - FSR402 sensor data
3 column - NTC10k temperature sensor data
4 column - accellerometer X data
5 column - accellerometer Y data
6 column - accellerometer Z data
1 column - time, ms
2 column - FSR402 sensor data
3 column - NTC10k temperature sensor data
4 column - accellerometer X data
5 column - accellerometer Y data
6 column - accellerometer Z data
agniusm
1 MW
So, poron is producing 18-20N of force measured. Thats 1.83kgf/2.54cm² and 2.04kgf/2.54cm².
Poron specification is 76kPa which is 0.775kgf/cm² or 1.968kgf/2.54cm² which is close to my observation. Can someone check my math here?
Poron specification is 76kPa which is 0.775kgf/cm² or 1.968kgf/2.54cm² which is close to my observation. Can someone check my math here?
agniusm
1 MW
Here is the data:
https://drive.google.com/open?id=0B56NVZIdTBFObXhKZE9OTUFmUXM
The acceleration data must be off. Sensor needs to be calibrated and my arduino to excel math might be crap
https://drive.google.com/open?id=0B56NVZIdTBFObXhKZE9OTUFmUXM
The acceleration data must be off. Sensor needs to be calibrated and my arduino to excel math might be crap
Attachments
agniusm
1 MW
Hm, no one has any insights on testing?
Will be making another die, probably making tabs in house:
Will be making another die, probably making tabs in house:
tomjasz
1 GW
Sometimes responses are quicker and some interesting feedback can be had on the FB forum.agniusm said:
agniusm
1 MW
Its on facebook as well also on russian electrotransport.ru
Hummina Shadeeba
1 MW
the 20 minute torture film starting with the 30 seconds of crying and the constant temp readings and the little motor yea I watched it. You could've stopped sooner!
Does that spinning gyration really simulate the loads it would encounter?
what do you think of using a greater pressure while using a harder rubber to hold better or in the interest of just using less space and material? how much pressure is it ok to put on an 18650?! makes me wonder if using the foam or rubber or whatever soft material is a good idea and maybe be simpler and more reliable to clamp the copper against the steel cell.
how thick is your rubber (there's no good shot of it alone) and how much pressure from wrench and then I guess disbursed evenly and at what on each tab in ft lbs?
Does that spinning gyration really simulate the loads it would encounter?
what do you think of using a greater pressure while using a harder rubber to hold better or in the interest of just using less space and material? how much pressure is it ok to put on an 18650?! makes me wonder if using the foam or rubber or whatever soft material is a good idea and maybe be simpler and more reliable to clamp the copper against the steel cell.
how thick is your rubber (there's no good shot of it alone) and how much pressure from wrench and then I guess disbursed evenly and at what on each tab in ft lbs?
agniusm
1 MW
I will not get into detail on materials, it was discussed here and on Snath's thread.
The simulated vibrations are to see how foam performs as compression method and from the chart i concluded that most impact to foams performance comes from temperature inside the battery and not the forces. Sure you could make it fail with the loads but if you would sustain those loads on the bike, you'd be least concerned about your battery, or you might be dead
Foam i use has low set properties, meaning it will last long without loosing its springiness. Most materials would wear out in time.
All the data of pressure on tabs is in earlier posts, its in SI units and if you are interested, convert them yourself online to whatever you like. I can repeat it here, 17-20 newtons / 2.54cm² or 1.73-2.03kgf/2.54cm²
P.S. To be more precise, sensor active area is 1.27cm²
The simulated vibrations are to see how foam performs as compression method and from the chart i concluded that most impact to foams performance comes from temperature inside the battery and not the forces. Sure you could make it fail with the loads but if you would sustain those loads on the bike, you'd be least concerned about your battery, or you might be dead
Foam i use has low set properties, meaning it will last long without loosing its springiness. Most materials would wear out in time.
All the data of pressure on tabs is in earlier posts, its in SI units and if you are interested, convert them yourself online to whatever you like. I can repeat it here, 17-20 newtons / 2.54cm² or 1.73-2.03kgf/2.54cm²
P.S. To be more precise, sensor active area is 1.27cm²
tomjasz
1 GW
Sadly this is a dead end. It was a pack i was really excited about. Making the Vruzend more attractive. I understand the reasons, but still....i just dont see the modular as very workable. You worked so hard on this.
agniusm
1 MW
To each their own. Its always good to have a choice. As far, i remember 6P was to big for you anyway..
tomjasz said:
P.S. you probably got alarmed by seeing pricing on the home page which is irrelevant to real pricing and it is there for my own better understanding how wordpress works.tomjasz said:
Hummina Shadeeba
1 MW
great thread and wanted to make something similar for a long time and finally did. another thread here.
agniusm
1 MW
This development has ended in most part and products are available. New thread with tests is here: https://endless-sphere.com/forums/viewtopic.php?f=31&t=88051&sid=2ea50b780347013e820015160aaa569a
And the shop is here: www.18650.lt
And the shop is here: www.18650.lt
tomjasz
1 GW
This has come so far and is impressive!
