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Discussion Starter #1 (Edited)
As part of the tricycle project, I'm looking at the option of making custom na-ion batteries. The production method would be entirely similar to li-ion batteries, so perhaps some of you that have done this already could help me with this.

I'm thinking of using the Tiamat batteries
http://www.tiamat-energy.com/
https://phys.org/news/2017-11-start-up-aims-sodium-ion-batteries.html

The Tiamat batteries are essentially 18650 format cells (the same cell type as in li-ion). I'm assuming both the na-ion and the li-ion have the same specs, so 1,5 Ah (1,5V x 1A), 65-68 mm long, 18mm thick
If I put 24 of these in series I get = 36V x 1A and if I use 13 of these 24-packs in parallell I get 36V x 13A, so 468 Watt/hr, which is similar to regular na-ion e-bike batteries. Of this 468 watt/hr, only 374 watt/hr is usable (20% DOD) which is actually too low as I need 420 watt/hr that is actually usable. So 36V x 17 Ah is better (612 watt/hr of which 489 watt/hr is usable). 17 ah ebike batteries are also quite standard, so it should be easy enough to find a charger for that too. 17 packs of 24 means 408 cells that need to be purchased.

I would also put in some more space than what's usual in between the cells to increase cooling; also added would be a fan (or 2) in front of the cells to increase air flow between the spaces when the vehicle is parked. When riding, air would flow naturally, so fans can be off, and air flows in via a separate pipe.

So, what "housings" are available for this sort of project (brands/models) in which I can place the cells in, along with mounting a fan or 2 and which have sufficient space in between the cells ?
Also, do I need to solder the batteries to a wire strip, ... ?
I want a decent connection, but if possible, prefer that the cells can still be removed if needed.
 

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If I put 24 of these in series I get = 36V x 1A and if I use 13 of these 24-packs in parallell I get 36V @ 13A, so 468Watt
I think you really should learn the difference between power (measured in units such as watts) and energy (measured in units such as watt-hours) so that your posts make sense.
 

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Discussion Starter #3 (Edited)
As part of the tricycle project, I'm looking at the option of making custom na-ion batteries. The production method would be entirely similar to li-ion batteries, so perhaps some of you that have done this already could help me with this.

I'm thinking of using the Tiamat batteries
http://www.tiamat-energy.com/
https://phys.org/news/2017-11-start-up-aims-sodium-ion-batteries.html

The Tiamat batteries are essentially 18650 format cells (the same cell type as in li-ion). I'm assuming both the na-ion and the li-ion have the same specs, so 1,5 Ah (1,5V x 1A), 65-68 mm long, 18mm thick
If I put 24 of these in series I get = 36V x 1A and if I use 13 of these 24-packs in parallell I get 36V x 13A, so 468 Watt/hr, which is similar to regular na-ion e-bike batteries. Of this 468 watt/hr, only 374 watt/hr is usable (20% DOD) which is actually too low as I need 420 watt/hr that is actually usable. So 36V x 17 Ah is better (612 watt/hr of which 489 watt/hr is usable). 17 ah ebike batteries are also quite standard, so it should be easy enough to find a charger for that too. 17 packs of 24 means 408 cells that need to be purchased.

I would also put in some more space than what's usual in between the cells to increase cooling; also added would be a fan (or 2) in front of the cells to increase air flow between the spaces when the vehicle is parked. When riding, air would flow naturally, so fans can be off, and air flows in via a separate pipe.

So, what "housings" are available for this sort of project (brands/models) in which I can place the cells in, along with mounting a fan or 2 and which have sufficient space in between the cells ?
Also, do I need to solder the batteries to a wire strip, ... ?
I want a decent connection, but if possible, prefer that the cells can still be removed if needed.

I also want to examine the possibility of doing the same for NIMH cells.
There are several brands, but Eneloop seems like the best one for me.
Eneloop (AA-size) cells are 1,2V x 2Ah, and 14,5 mm in diameter and 50,5 mm long.
So 30 of these in series = 36V
8 of these in parallel = 36V x 16 Ah
That means energy = 576 watt, usable = 460 watt/hr
Number of cells required = 240 cells
A same charger as those that work on the Panasonic 36V 17 Ah battery can probably be used.

Same questions as for the na-ion's apply: which housing can I buy for this, and do they need to be soldered on, ... ?
 
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