Search found 219 matches

by Frank
Oct 07 2021 9:23am
Forum: EScooter/EMotorcycle Build Threads
Topic: Suzuki GSX-R e899 K2
Replies: 470
Views: 87564

Re: Suzuki GSX-R e899 K2

Why?
by Frank
Aug 01 2021 2:56am
Forum: EBike Technical
Topic: Are Anderson PowerPole connectors the de-facto standard?
Replies: 46
Views: 1045

Re: Are Anderson PowerPole connectors the de-facto standard?

I've routinely run hundreds of amps through PP's on race vehicles for many years and also use them for connecting a charger albeit at only a few amps.

Sent from my SM-T380 using Tapatalk

by Frank
Jul 09 2021 5:35am
Forum: Battery Technology
Topic: Molicel P42a cycle test
Replies: 51
Views: 3307

Re: Molicel P42a cycle test

Why do you think the charge is always less than the discharge? Shouldn't it be the other way around? Or am I misreading the numbers?

Sent from my SM-T380 using Tapatalk

by Frank
May 30 2021 5:27am
Forum: Battery Technology
Topic: Meanwell HLG-320H Series Combination Charging
Replies: 8
Views: 363

Re: Meanwell HLG-320H Series Combination Charging

I'm also interested in this concept to charge a 20S pack (82-84V) - any recommendations? I'm also hunting around for a decent fixed-voltage charger but having the slight bit of adjustment typically found in a PS would be nice. (thanks)
by Frank
May 17 2021 12:09pm
Forum: Battery Technology
Topic: ANT BMS QUESTION - please help!!
Replies: 8
Views: 409

Re: ANT BMS QUESTION - please help!!

Just to confirm - this method keeps the pack in balance but does nothing about the unequal power draw. Isn't there a way to totally disconnect the BMS to eliminate power draw during storage? I'm asking as I have one of the older ones (just installed, just downloaded the app today) and the newer vers...
by Frank
May 15 2021 1:45pm
Forum: Battery Technology
Topic: Compression of pouch cells, info/data
Replies: 52
Views: 1203

Re: Spot Welding Copper Strips to 18650 Battery Cells

I've never heard of anyone cranking up pressure like that on pouch cells.

My drag race (Lonestar) cells are lightly compressed in a polycarbonate enclosure. It's stiff enough to inhibit swelling but nowhere near that kind of pressure.

I wonder if Zero actually does that?
by Frank
May 15 2021 12:56pm
Forum: Battery Technology
Topic: Compression of pouch cells, info/data
Replies: 52
Views: 1203

Re: Spot Welding Copper Strips to 18650 Battery Cells

I communicated to a battery engineer from Zero motorcycles and and 100-psi is a helpful goal. They used flat pouch Farasis cells, and then potted them after testing. He mentioned anything is better than nothing, and not much of a benefit above that. That sounds insane! It implies that a pack with c...
by Frank
May 15 2021 6:25am
Forum: Battery Technology
Topic: Compression of pouch cells, info/data
Replies: 52
Views: 1203

Re: Spot Welding Copper Strips to 18650 Battery Cells

Any chance you could post a picture of this? I'm having trouble visualizing it. (thanks)
by Frank
May 08 2021 1:47pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

Good idea, how did you bore out the tabs?

Nice video on the website, BTW! :wink:
by Frank
May 08 2021 1:27pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

@garolittle: Nice looking pack - I'm curious: did you "dent" the copper over each cell (to conform to the outline created by the cell holder) with a small hammer or other tool? Or was the welding pressure enough to ensure the copper conformed as well as possible to the top of the cell? (th...
by Frank
Apr 29 2021 9:27am
Forum: Items for Sale - Used
Topic: N.E.S.E. 21700 Cell Holder Modules 5P PETG
Replies: 1
Views: 540

Re: N.E.S.E. 21700 Cell Holder Modules 5P PETG

These will fit in a medium flat-rate box for shipping inside the US. $25 should cover everything. I may be having problems with my PM's and am working to understand what's going on. I'm receiving but don't think my replies are going out. [EDIT] - I've just seen that replies don't go "out" ...
by Frank
Apr 18 2021 5:43pm
Forum: Items for Sale - Used
Topic: N.E.S.E. 21700 Cell Holder Modules 5P PETG
Replies: 1
Views: 540

N.E.S.E. 21700 Cell Holder Modules 5P PETG

I printed these from PETG thinking I would try using the N.E.S.E. cell holders for a project but decided to go a different route. I have twelve (12) of these, eleven are unvented and one of them is vented. They're all 5P holders, no hardware included. Some of them have a bit of black electrical tape...
by Frank
Mar 16 2021 7:19am
Forum: Battery Technology
Topic: jonescg's cylindrical cell build thread
Replies: 65
Views: 3668

Re: jonescg's cylindrical cell build thread

Great news - congratulations.
by Frank
Mar 13 2021 4:14pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

That would certainly help, good idea.
by Frank
Mar 13 2021 4:05pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

From my understanding, current follows the path of least resistance. With this is mind, the copper is in contact with the nickel strip on the battery side as well as the nickel that is wrapped around. Therefore the current path would travel from the battery, then through 0.15 thickness of nickel at...
by Frank
Mar 13 2021 2:03pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

The way it is now current flows through each nickel strip to the copper from each end and each cell should contribute equally. If you had for example, a 4P configuration, current from the middle two cells would have to flow past the outer two cells via the nickel strips to reach the copper. It would...
by Frank
Mar 13 2021 12:53pm
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

It seems to me that would work but only for a 2P design. What thickness copper is that? I'm surprised the sandwich technique did not work.
by Frank
Feb 23 2021 7:43am
Forum: Battery Technology
Topic: jonescg's cylindrical cell build thread
Replies: 65
Views: 3668

Re: jonescg's cylindrical cell build thread

Yikes, that is kind of expensive, especially if you have to buy mass-quantities! (cue Conehead reference...) I've used plain old black RTV before when building a hybrid solar panel (liquid cooled PV using reflectors to increase insolation area) and that worked pretty well as a thermal conductor. I t...
by Frank
Feb 22 2021 11:13am
Forum: Battery Technology
Topic: jonescg's cylindrical cell build thread
Replies: 65
Views: 3668

Re: jonescg's cylindrical cell build thread

Chris, have you shared what type of thermally conductive epoxy you're using? Did you do any testing? (thanks)
by Frank
Feb 21 2021 8:34am
Forum: Battery Technology
Topic: jonescg's cylindrical cell build thread
Replies: 65
Views: 3668

Re: jonescg's cylindrical cell build thread

The more I think about it, the more I like the idea of potting the connection ends. You get a more stable structure, electrical connections should be immune from vibratory damage and you realize heat conduction out of the pack. I hope you keep updating this thread Chris as the 10% weight penalty see...
by Frank
Feb 19 2021 7:48am
Forum: Battery Technology
Topic: First Battery Build 21700 Molicel P42A
Replies: 73
Views: 3604

Re: First Battery Build 21700 Molicel P42A

That's weird - it wasn't when I checked earlier! I guess that's normal when stock flows in and out all the time.
by Frank
Feb 18 2021 3:21pm
Forum: Battery Technology
Topic: First Battery Build 21700 Molicel P42A
Replies: 73
Views: 3604

Re: First Battery Build 21700 Molicel P42A

I've been wondering the same thing about measuring P42A's before assembling. The meter is a good idea but unfortunately the SM8124 seems to be unavailable, would you have any other recommendations for a meter? Does anyone use Allosun?
by Frank
Feb 11 2021 8:57am
Forum: EBike Build Threads
Topic: Building A Ludicrous 14s2p SPIM08hp battery
Replies: 44
Views: 5172

Re: Building A Ludicrous 14s2p SPIM08hp battery

I think the cell tabs are already slotted. The machine screws clamp the U-shaped copper to the tabs. The plastic spacer prevents the whole thing from collapsing. I used the cells with holders but recall seeing other packs with bare cells. IIRC one guy used rivets somehow. Although the spacing was ok...
by Frank
Feb 10 2021 11:18am
Forum: EBike Build Threads
Topic: Building A Ludicrous 14s2p SPIM08hp battery
Replies: 44
Views: 5172

Re: Building A Ludicrous 14s2p SPIM08hp battery

I don't have any pictures, but I made 1P series connections by bending copper sheet into a "U" shape then bolted the tabs together with two 5 mm machine screws. I 3-d printed some plastic spacers that went between the tabs to help alignment (these fit inside the "U"). I seem to r...
by Frank
Feb 09 2021 7:50am
Forum: Battery Technology
Topic: Spot Welding Copper Strips to 18650 Battery Cells
Replies: 545
Views: 94670

Re: Spot Welding Copper Strips to 18650 Battery Cells

Why might this welder work on .4 mm copper at those settings and the kWeld won't?

I'm not home right now but have welded thinner copper using the "sandwich" technique at those energy levels (not sure of the pulse time) but I'm pretty sure it wouldn't work for .4 mm thick stuff.