More Power, Capacity and Less Expensive (21700)

[eMark]

I explained how to calculate the Wh for a single cell previously.

Made corrections in previous post (in green) and added another question (in green). What is your Wh rating (using 3.80V) for a 14S14P P42A battery ? Is it 14P x 4.2A x 3.80V = 223.44Wh = 14S14P P42A costing $980 for 196 cells. So what is the $ cost for 1 kWh ?

Still digesting DDs full-featured red-lettered post :thumb:

 

[Hillhater]

Using Molicel’s data from their spec sheet, each cell has a “typical” capacity of 15.5 Wh.
So a pack using 196 cells ( of any configuration ) will have ..15.5 x 196 = 3038 Wh (3.038 kWh)
BUT, the usable capacity will depend on what charge voltage is used , and what LVC is set .
And at $980 cost, is equivalent to $980 /3.038 = $322.6 per kWh

 

[eMark]

I explained how to calculate the Wh for a single cell previously.

Made corrections in previous post (in green) and added another question (in green). Using your 3.80V rating for a 14S14P P42A battery arriving at 15.96Wh per cell 14P x 4.2A = 58.8Ah, 14S x 3.80V = 58.8V ... 58.8Ah x 58.8V = 3457.44Wh = 14S14P P42A 196 cells $5ea = $980. So using those figures the cost for 1kWh is 28.92% of $980 = 1kWh costs $283.45

However, to be more "nominal" when figuring Wh of one P42A cell one should figure both "nominal" V and "nominal" Ah rating. Using 85.714% of both 4.20V and 4.20Ah = 3.60V and 3.60Ah ... 90.476% = 3.80V and 3.80Ah (your "nominal") ... 3.80V x 3.80Ah = 14.44Wh more realistic to real-life application if cut-off voltage is 47.6V = 3.4V per cell (14.44Wh x 196 P42A cells = 2830.24Wh from a 14S14P battery).

Your use of 3.80V for arriving at 15.96Wh for one P42a cell implies that your cut-off voltage was 3.4V ...

4.2V (full)
4.1V
4.0V
3.9V
3.8V
3.7V
3.6V
3.5V
3.4V (cut-off)

As sp posted last year DIY builders should think more in terms of Wh as e-bike DCBL motors are rated in Wh (500Wh, 750Wh, 1000Wh). For example with a 750Wh DCBL motor it would be nice to know how many P42A cells are needed in each p-group in a 14S DIY build to theoretically achieve 500Wh for 1hr of continuous raw performance

Using 3.80V and 4.2Ah for a 14S P42A build with 9 cell p-groups = 529.2Wh of raw performance for 1 hour (29.2Wh of wasted energy). Is my figuring improving ?

 

[Hillhater]

.Is my figuring improving ?

No ! You are still thinking that cell capacity and voltage have a linear relationship ( straight line graph)... when they dont.
And you dont seem to read replies .
Why dont you just stick to using the data from Molicel ?
Your 14s 9p example would have 1,953 Wh ( 126 cells @ 15.5 Wh )

 

[eMark]

You are still thinking that cell capacity and voltage have a linear relationship ( straight line graph)... when they dont. Your 14s 9p example would have 1,953 Wh ( 126 cells @ 15.5 Wh )

My Molicel P42A example was with a 14S14P (with nominal V and nominal mAh). It would still have a declining curve from say 4.1v per cell to 3.0V and from say 4100mAh per cell to 1000mAh per cell. Maybe you were dreaming (14S9P). Are you color blind to (green) in my previous post ?

Your 14s 9p example would have 1,953 Wh ( 126 cells @ 15.5 Wh )

Did you even read my post or your rare form of humor to misrepresent

Perhaps you need to see an eye doctor. Could it be that you’re color blind not only to green, but also to red (DDs red-letter comments). You never responded to portions of his post directed to your comment(s).

 

[eMark]

A Molicell 2600mAh 18650... @ @ 5$/ cell..... 5$/9.3wH = $537/kWh. That is the retail price of a single Molicel P26A (2021-dated) - 35A 2600mAh 18650. 537$/kWh. this is why the 4200 interested me, the lower and competitive price per kWh.

Now dont get me wrong. If I could afford an 18650 pack I for sure would build one.. but I wont at 500$ + per kWh.

Comparing a li-ion e-bike battery to a lipo pouch car battery is (IMO) not a fair comparison. Can't envision what kind of "tools" use your lipo pouch builds ... thought your insightful post about your lipo pouch builds was also applicable to e-bike builds ... correct or maybe not ??

Was there sufficient reason WAY BACK then why this ES tread of 2017 about an e-bike lipo pouch battery … https://endless-sphere.com/forums/viewtopic.php?t=86067 ... only received 1 reply and not until 2019 by bogus105 ...

And? Was there an explosion or what? No more updates How is the battery pack? Are these pouch cells good in real life?

Although it has had 1846 views since 2017 will lipo pouch cells for ebikes ever gain traction? What has to change for lipo pouch cells to be as popular as li-ion 1865/2170 cells for e-bike DIY battery builds (e.g. say 10S to 14S). Does the Harley LiveWire use a pouch cell battery ?

Maybe it’s about time for you to start a 2022 lipo pouch ES Thread for e-bike DIY builds -- lipo pouch builds for more conservative packs than 24S (say 10S-14S). Assuming a lipo pouch e-bike DIY battery is as competitive in $ and cycle life (e.g. 10S-16S) than a 1865 or 2170 DIY build ...

Here is larger image of your prized Chevy VOLT pouch cell in place of your thumbnail image.
Did i understand you to say that GM VOLT lipo pouch cells only set you back $9.00 a piece ...

THANKS Again for your very informative post. Still digesting it’s significance for a modest e-bike battery DIY build (say 10S, 12S or 14S ... without K-weld :wink
_____________

PS: What's Your Connection With GMC :wink: https://www.youtube.com/watch?v=DZuJivIwV8o

My first and only GM was a 1965 Pontiac Tempest Custom 2dr Hardtop with 327 (performance small block 250hp). To buy a good one now (if you can find one) can cost up to $50K.

 

[DogDipstick]

Here is a link to a for sale thread I closed a while back. Shows a bunch more pics. yeah, Ron has started a pouch cell build thread here in the past for sure.

Im here in this thread to learn about round cells though. It is important skills, to me, as a laborer trying to sell my battery repair skills.

Although it has had 1846 views since 2017 will lipo pouch cells for ebikes ever gain traction? What has to change for lipo pouch cells to be as popu...

Maybe it’s about time for you to start a ...Assuming a...

understand you to say that ...ack $9.00 a piece......
.

Less. Less even. Cells on my bike I paid 140$, for ( 36) 15Ah, cells. Built from torn up modules from GreenTec. So that is like... $3.88$ ea. $3.88 for a 15Ah, 15C+, 3.7v nominal, 55.5 watt hour cell. I have 20 on my bike. So I paid *77.77$* for my 1280wH battery... minus labor. Hit it for 8000w+ (more) every day.

I had another, but it got closed ( Cell for sale thread). That one had over ten thousand views. That was 2018? I can build and sell packs pretty much all day If I wanted that responsibility. Check pics and info for more. I do have about 100-150 cells right now.
https://endless-sphere.com/forums/viewtopic.php?f=9&t=107299&p=1570713&hilit=Chevrolet#p1570713

However, round cells seem to be where the money is at. Rebuilding packs and fixing tool packs. I honestly have a pack right here I promised to rebuild and I have to buy cells for ( 18650s).

 

[Hillhater]

Perhaps you need to see an eye doctor. Could it be that you’re color blind not only to green, but also to red (DDs red-letter comments). You never responded to portions of his post directed to your comment(s).

We obviously have a terminology/ language problem here
There was nothing in DDs red comments for me to respond to...other than to thank him for replying !
.. And which particular shade of green would that be ?
...And which previous post are you refering to ?
But no need to reply, as you obviously know everything you need to,..
...so i wont be responding further .

 

[eMark]

deleted due to double post error due to time lapse ???

 

[eMark]

changed to Molicel P35A ... due to time lapse the edited correction was posted again

 

[eMark]

Here is a link to a for sale thread I closed a while back. Shows a bunch more pics ... https://endless-sphere.com/forums/viewtopic.php?f=9&t=107299&p=1570713&hilit=Chevrolet#p1570713

• In the Volt cells, is the separator material, and a less volatile and more tolerant electrolyte solution that doesn't settle or migrate with temp swings (part of why they are more expensive). The maximum temperature before venting is 160*C. They also were pushing self-healing ... so the electrolyte will recombine under some conditions minimizing swelling. The goal was 5000+ cycles for production, and the cells were warranted for 8 years or 80K mile.

Because of previous experience with RC Lipo my come-away is that any noticeable RC Lipo puffing was due to abuse. Your above quote implies that the safety factor of pouch li-ion swelling isn't as much of a problem as once. So it really isn't necessary to compress pouch cells during DIY fabrication. Exception being some e-bike mindset (raw performance) as part of its intended application.

Im here in this thread to learn about round cells though. It is important skills, to me, as a laborer trying to sell my battery repair skills.

However, round cells seem to be where the money is at. Rebuilding packs and fixing tool packs. I honestly have a pack right here I promised to rebuild and I have to buy cells for ( 18650s).

If tool packs had enuf room for 2170s instead of 1865s you would make potential clients very happy getting a better battery than new ... making it worth your labor & parts cost ...
(that's a BIG IF assuming that it is even possible and legally OK to refurbish a brand name lithium tool pack)

Your suggestion of the Molicell P26A 18650 35A rated power cell :thumb: https://www.18650batterystore.com/products/molicel-p26a?utm_campaign=859501437&utm_source=g_c&utm_medium=cpc&utm_content=201043132925&utm_term=_&adgroupid=43081474946&gclid=CjwKCAjw682TBhATEiwA9crl3wrRxNH-KLVgtVLtCC8kzoIO3yKRxVQpK95wDaC1jfk8VGTjDUFvWBoCw-sQAvD_BwE ... 100+ $3.59 (probably as good, if not better, than the original cells in most tool pack batteries.

A Milwaukee M28 28-Volt Lithium-Ion XC Extended Capacity Battery Pack 3.0Ah ($180) should be worth the time and expense to refurbish using Molicell P26A (2600mAh) 35A rated power cells.

Must figure eight 3000mAh high energy cells in series = 28V. It would make good sense/cents that some of the new tool packs like this Milwaukee M28 use 2170 size cells :thumb:

 

[eMark]

if i wasn't such a meticulous proof reader / editor double posting wouldn't happen and wouldn't have to delete

 

[eMark]

A Molicell 2600mAh 18650... @ @ 5$/ cell..... 5$/9.3wH = $537/kWh. That is the retail price of a single Molicel P26A (2021-dated) - 35A 2600mAh 18650. 537$/kWh. this is why the 4200 interested me, the lower and competitive price per kWh.

I build tool packs, and yes, a powerful cylindrical cell pack interests me for it is not bulky and if you can afford it it is a very long lasting option for a good ebike. I own a K-Weld and do tool packs... and would build with the cylindrical cell.. IF...

This is a popular powerful Vape cell. Recently tested by our friend Mooch. 537$ / kWh.. retail from a reliable source ( not fake or clones) . Molicel P26A 18650 2600mAh 35A Battery... 5$ ea.

https://www.18650batterystore.com/collections/featured-products/products/molicel-p26a
https://www.e-cigarette-forum.com/threads/bench-test-results-molicel-p26a-2021-dated-35a-2600mah-18650.974009/?fbclid=IwAR3wY2CpQE_Mp9Kn_cum0_dbvHKMjVXptRH1JzQYjpfGEz03fAPGFYYzJAU

Even the home handyperson expects their 18V tool battery to be at least 3.0Ah (not 2.6Ah). IF only Molicel manufacturered an 1865 P32A rated at 30amp MCD for $5.39 (100+), but no such luck --

Better yet if only an 18V repair only MANLY packs -- 5s2p 18V with 5.2Ah rating. Ten P26A 45A rated cells from BatteryStore ($3.59 in 100+ quantity) = $35.90 for a 5s2p rebuild ...
(that must have been what you had in mind all along ... a win/win for both the builder and client) --

It might even be worth your time to rebuild an 18V 5s2p tool battery with 1865s. Better yet whenever possible use 2170s when rebuillding any Li-ion tool pack ( e.g. Five P42A cells from BatteryStore $4.87 in 100+ quantity = $24.35 = 18V 4.2Ah rating :thumb:

Using 2170s instead of 1865s = more Power, Capacity, Happy clients (and more Profit) -- :thumb:

Here's a youtube that you could've just as well uploaded yourself ...
DIY 21700 POWER TOOLS MAKITA BATTERY
https://www.youtube.com/watch?v=W6ueHJ2VNg0

Here's another youtube showing what tool packs are 21700 and 18650 and the reasoning ...
What's Inside Tool Batteries? Milwaukee FLEX DeWalt Makita Snap-On [18650 21700 ??]
https://www.youtube.com/watch?v=Plhxnrba2D8

Tool Battery Manufacturers Welcome 21700 for the Reasons in the Thread Title --

 

[DogDipstick]

Here's another youtube showing what tool packs are 21700 and 18650 and the reasoning ...
What's Inside Tool Batteries? Milwaukee FLEX DeWalt Makita Snap-On [18650 21700 ??]
https://www.youtube.com/watch?v=Plhxnrba2D8

Tool Battery Manufacturers Welcome 21700 for the Reasons in the Thread Title --

Thats a good one. I'm saving that vid for future ref. The 21700 in the Dewalts. Yup. A "new replacement" no name pack is 40$, a replacement Dewalt is 80-120$ depending ont eh Ah capacity, they come in 2.0, 3.0, 4.0, ect... 5Ah... $, but If I can get the materials cost down under 20$ ea pack I can make a very good profit from the labor.

 

[eMark]

Here's another youtube showing what tool packs are 21700 and 18650 and the reasoning ...
What's Inside Tool Batteries? Milwaukee FLEX DeWalt Makita Snap-On [18650 21700 ??]
https://www.youtube.com/watch?v=Plhxnrba2D8

Tool Battery Manufacturers Welcome 21700 for the Reasons in the Thread Title --

Thats a good one. I'm saving that vid for future ref. The 21700 in the Dewalts. Yup. A "new replacement" no name pack is 40$, a replacement Dewalt is 80-120$ depending ont eh Ah capacity, they come in 2.0, 3.0, 4.0, ect... 5Ah... $, but If I can get the materials cost down under 20$ ea pack I can make a very good profit from the labor.

This youtube ... Your BUYING and USING Milwaukee M18 Batteries ALL WRONG! (stop doing this) is hard to argue against in that for the money an upgraded more powerful e-tool battery (2170) is unquestionably a BETTER investment than the less powerful 1865 battery that came with the Milwaukee (or came with other POWER e-tools).

To get his point across he apparently felt he had to RAISE his Voice a couple pitches to persuade viewers that the price differential between yesterday's (obsolete?) 1865 power e-tool battery and todays upgraded 2170 Power e-Tool Battery is worth the extra cost. More BANG for the buck.

Example of yesterdays 1865 pack still $139 and todays upgraded Milwaukee 2170 $149 ... https://www.youtube.com/watch?v=TrYpAckWe6M ... (8:00 to 10:00).