ways to make a battery pack????

[Hugh-Jassman]

I saw these conectors on an ES thread (2WD Electric Yuba Mundo Build), but I am not finding them on the internet. What are they? where can I get them?
But most importntly: are they scewed into the battery cells? I don't want to have to build a capacitor welder. But is putting screws into the cells safe?
It looks like these batterys are larger than 18650 cells....true?? what are they?

 

[Jon NCal]

headway

 

[Hugh-Jassman]

the realy big question here is: did he actualy just srew the srews into the battery posts?

 

[999zip999]

Yes there are lifepo4 heavy long lasting. Over rated c-rate. If you have a lot of room ? Check the pics at headway headquarters. They sell them can't vouch for them.

 

[Hugh-Jassman]

so I am going to have to buy a pack of 4 18650 cells unless some one can tell me for sure that I can put screws into these cells. I only need it for a strobe light to keep people from running me down at this one intersection.

But I was hoping to find a way to make larger packs with out having to weld them.

 

[Hugh-Jassman]

Headway is goin gto woole sale only now.....500 pieces at a time

 

[999zip999]

YES screw tops.

 

[Hugh-Jassman]

Are these the new Tesla cells? or are they making somehting differnet? (called ‘2170’)
https://electrek.co/2017/01/04/tesla-2170-battery-cell-production-gigafactory-model-3/

 

[Matador]

Are these the new Tesla cells? or are they making somehting differnet? (called ‘2170’)
https://electrek.co/2017/01/04/tesla-2170-battery-cell-production-gigafactory-model-3/

I Heard it'll eventually be in the newer Tesla versions, but right now 21700 ("2170" is sort of a misnomer) are around 4750 mAh, 75 g weight and 24.245 cc volume ... While our good old 18650's can reach capacities of around 3450 mAh, weight 45-50 g and are 16.54cc volume. I guess also LiNiCoAlO2 chemistry also.

http://i.stack.imgur.com/9iobu.jpg

Funny thing is, Tesla would be actually going for cells that have LESS ENERGY DENSITY ?

They would be going from 208.6 to 186.0 mAh/mL in volumetric energy density (that's from 751 to 670 Wh/L) and from 69.0 to 63.3 mAh/g in massic energy density (that's 248.4 to 228.0 Wh/kg). So choosing cells that have 10.87% less energy density per volume units and 8.2% less energy density per mass units. I guess the advantage of 21700's is they may cost less $ per Wh in the end... An less shell weight... But then, we have to ask them if it's really the reason for changing cell format...

 

[boisrondevens]

I have headways, bus bar and plastic holder for sale.
PM me if interested

 

[Hugh-Jassman]

What chemistry is the Tesla 2170 cell? LiFeMgPO4 Lithium Magnisium Phosphate? They should be putting bolt ends on them. How do they conect in their packs?

 

[tomjasz]

http://www.batteryblocs.com

https://youtu.be/542D37mbegM

 

[spinningmagnets]

The new 21700 Tesla cells are almost identical to the old Tesla 18650 cells, just a little larger by a few mm in diameter and length.

The Headway cells are a LiFePO4 chemistry, and yes, they have screw-ends, which make them easy to bolt together. They have a lower voltage (3.3V?) instead of the nominal 3.7V we normally find in 18650 cells with NMC, NCA, LiMn and LiPo chemistries. I would not get Headways for high-performance, but if their output in volts and amps works for your project, they can last many years.

The Headway 38120 cell is 10-Ah each @ 3.3V, it is 38mm in diameter, and 120mm long. They are large. 25mm is about one inch so...1.5 inches diameter, and roughly five inches long.

Here are the Headway parts you were asking about http://www.headway-headquarters.com/brands/Headway.html