Tesla Sanyo 20700 Batteries

[Hunka Hunka Burning Love]

I was watching this video about the Meepo Penny board, and it was interesting to note that Kieran uses Tesla Sanyo 20700 cells instead of the more commonly used 18650's we all have.  It would be sweet if the new Gotway Tesla used the same cells to increase range.

 

[steve454]

On 9/11/2017 at 12:30 AM, Hunka Hunka Burning Love said:

I was watching this video about the Meepo Penny board, and it was interesting to note that Kieran uses Tesla Sanyo 20700 cells instead of the more commonly used 18650's we all have.  It would be sweet if the new Gotway Tesla used the same cells to increase range.

 

The IPS I5 can be ordered with the 20700 batteries, or the 18650's.  The larger batteries give more wh and range.  Costs only a little more, @Tilmann has that version,  IFRC.

[houseofjob]

19 minutes ago, steve454 said:

The IPS I5 can be ordered with the 20700 batteries, or the 18650's.  The larger batteries give more wh and range.  Costs only a little more, @Tilmann has that version,  IFRC.

As do I, and the range is pretty impressive, albeit partly due to only being able to go 20kph max.

 

Portable Electric Vehicle YouTube channel did a swap for 20700B battery pack used in an InBoard M1 (e-board) that doubles the range:

 

[Hunka Hunka Burning Love]

I wonder when all the big EUC makers will eventually switch over.  Double the range doesn't sound too bad!   Will the 2170 cells reach other markets too?  What's up with all the downvotes?  

BTW Meepo penny with the 20700 isn't available any more.  

[mezzanine]

I really want to eventually upgrade my V8 with a new battery pack and would love more information on the availability of these batteries as an option.  Don't know if I'm feeling adventurous enough to go about building my own pack, but I'm tempted.  Give the V8 a little more range, and for me it's the perfect wheel. 

[meepmeepmayer]

The packs and their housing (including the wheel shell itself) are usually built to fit the specific cell size. So I don't expect 20700s to happen to fit into a housing built for 18650s efficiently, which ist the point of the bigger cells after all (less wasted space to used "chemical" space, the chemistry is the same in all cells).

But maybe if you're lucky it will work. There's a thread about a V8 battery extension in the diy forum here, with lots of pictures of the battery compartment.

[US69]

4 hours ago, mezzanine said:

I really want to eventually upgrade my V8 with a new battery pack and would love more information on the availability of these batteries as an option.  Don't know if I'm feeling adventurous enough to go about building my own pack, but I'm tempted.  Give the V8 a little more range, and for me it's the perfect wheel. 

I would not go for the 20700...

Instead of changing all 18650 to 20700...i would throw 20 cells of 18650 more in! Than you have more capacity plus one more seriell pack...20S3P instead of 20S2P.

That allready has been done and is documented somewhere here....

[houseofjob]

8 hours ago, Hunka Hunka Burning Love said:

I wonder when all the big EUC makers will eventually switch over.

Probably when they become cheaper by the bulk I'm guessing...

 

8 hours ago, Hunka Hunka Burning Love said:

What's up with all the downvotes?  

No clue, just paying back the favor here. 

[US69]

8 hours ago, Hunka Hunka Burning Love said:

wonder when all the big EUC makers will eventually switch over.  Double the range doesn't sound too bad!   Will the 2170 cells reach other markets too?  What's up with all the downvotes?  

Why should they Switch over? You see, the mah(range) jumps from 3500mah to 4000-4250mah...thats about 20% more!

BUT: The 2170 (or 20700) is also about the same percentage heavier and bigger! So there is no WIN Situation...ist the same Watthour per Volumen/weight Ratio.

 

The only Thing where i can see a real Advantage is on the wheels which only have a "one parallel" battery System settup....like the IPs I5. (where they use it!)

Here the new 20700 cells gives you an Advantage as they allow a higher max draw of Amps.

 

This Advantage goes away on bigger wheels where multiple parallel battery Systems share the Amperage....so that a high draw cell is not needed.

[mezzanine]

4 hours ago, meepmeepmayer said:

The packs and their housing (including the wheel shell itself) are usually built to fit the specific cell size. So I don't expect 20700s to happen to fit into a housing built for 18650s efficiently, which ist the point of the bigger cells after all (less wasted space to used "chemical" space, the chemistry is the same in all cells).

But maybe if you're lucky it will work. There's a thread about a V8 battery extension in the diy forum here, with lots of pictures of the battery compartment.

 

I didn't even realize that the batteries were two different sizes.  And I'm the guy talking about building my own battery pack over here. 

Like KS69 observed, the increased size of the 20700 isn't an improvement in volume/weight per wh. 

I've read that thread about the guy who did the custom battery very closely.  I wish he offered his services.  If I decide to get ambitious, I may build a few batteries and sell a couple to others who would also like to upgrade.  I'd start ordering stuff in maybe a month with the idea of having something six months now.  We'll see.  

[WARPed1701D]

27 minutes ago, mezzanine said:

 

I didn't even realize that the batteries were two different sizes.  And I'm the guy talking about building my own battery pack over here. 

Like KS69 observed, the increased size of the 20700 isn't an improvement in volume/weight per wh. 

I've read that thread about the guy who did the custom battery very closely.  I wish he offered his services.  If I decide to get ambitious, I may build a few batteries and sell a couple to others who would also like to upgrade.  I'd start ordering stuff in maybe a month with the idea of having something six months now.  We'll see.  

Unless you are a skilled electronic engineer with a good grasp of the properties and behaviour of cells and BMSs I wouldn't sell packs to others. Poorly built packs can be a huge fire risk and you would be opening yourself up to being liable if something were to happen.

[Keith]

11 minutes ago, WARPed1701D said:

Unless you are a skilled electronic engineer with a good grasp of the properties and behaviour of cells and BMSs I wouldn't sell packs to others. Poorly built packs can be a huge fire risk and you would be opening yourself up to being liable if something were to happen.

@mezzanine  I absolutely agree with @WARPed1701DThe only safe way to join cells is by spotwelding with nickel strips which gets very expensive unless you are able to build your own spotwelder or buy tabbed batteries. I shudder every time I see someone soldering them together as Lithium Ion cells are very easily damaged and then become a fire risk.

[WARPed1701D]

I would be more inclined to become efficient in swapping the V8 pack out with a second official pack. I'm sure that with some initiative and minor mods to the wheel it could be a <5 minute endeavor. I believe Stan does it for longer rides in around 10 minutes. Not as convenient but not far from it either.

[meepmeepmayer]

1 hour ago, mezzanine said:

 

I didn't even realize that the batteries were two different sizes.  And I'm the guy talking about building my own battery pack over here. 

20700 = 20mm wide (diameter), 70mm long

18650 = 18mm wide, 65mm long

2170 (not 21700 for some reason) = take a guess

Would be nice if you could just replace cells with 20% better ones, but that doesn't work here

The idea is (I believe), if you optimize cell dimensions, you should theoretically get a little increase in chemically useful volume to useless volume (air between the cells, cell casing, whatever) so effectively denser battery packs. I don't think there are major performance differences per useful chemical volume, it's the same stuff inside after all. But the different sizes are made for whatever reasons - to match/fit better into whatever they should (think of an e-bike where the cells have to fit and ideally fill out the metal pipes the bike is made of), maybe cost advantages in production, exclusivity and advertising reasons, idk.

[Lukas83]

5 hours ago, meepmeepmayer said:

20700 = 20mm wide (diameter), 70mm long

18650 = 18mm wide, 65mm long

2170 (not 21700 for some reason) = take a guess

Would be nice if you could just replace cells with 20% better ones, but that doesn't work here

The idea is (I believe), if you optimize cell dimensions, you should theoretically get a little increase in chemically useful volume to useless volume (air between the cells, cell casing, whatever) so effectively denser battery packs. I don't think there are major performance differences per useful chemical volume, it's the same stuff inside after all. But the different sizes are made for whatever reasons - to match/fit better into whatever they should (think of an e-bike where the cells have to fit and ideally fill out the metal pipes the bike is made of), maybe cost advantages in production, exclusivity and advertising reasons, idk.

yeah especially in small housings like a box mod / electronic cigarette ...im vaping since 2010 and 20700 is definitely an improvement in power and overall capacity...a lot of guys in the vaping scene already say that 20700s are the future... 

But in an euc i don't see improvements for the actual 18650 made wheels, except they change the design and housings for the batteries and save some space / packs.