"Tabless cell" the new new In lithium ion Tech

[Battery_Mooch]

@SternWake

Milwaukee should be getting the Grade A JP40’s, I’d think.

Absolutely.

@SternWake

Be interesting to see and measure their series connects, and compare to the Copper nickel sandwich in the custom EVE pack.

Agreed. Though the spot welds in the custom pack have a MUCH higher resistance than the huge laser welds in the other pack. IIRC that the other pack had laser welds.

@SternWake

The Modded Molicel 5s1p P28 pack smoking the Samsung 2p and 3p packs is also satisfying.

Moli’s are great cells, durable as heck too.

[SternWake]

The 1p Eve40pl custom battery performing nearly equally to the Forge 2p JP40 in that specific tool, makes me think the copper nickel sandwich in the custom, and wiring to from BMS to output terminals is perhaps lesser overall resistance than the factory Milwaukee.

But maybe that Milwaukee forge 8.0 battery has a hundred + cycles and 14 months of age on it, making the comparison unfair.

[SternWake]

Torque Test channel has a new video out, Centering on Tabless cell power tool battery packs.

Interesting disassembly of some of them too, especially the Bosch.

Testing the HYPE behind new "tabless" power tool batteries

[Battery_Mooch]

@SternWake

Interesting disassembly of some of them too, especially the Bosch.

The Bosch pack that was disassembled is not the 18V+ tabless-cell pack, it’s just the standard 18V pack, so the performance was understandably lacking. They pinned a comment regarding this IIRC.

[SternWake]

I thought the performance difference was interesting, as perhaps a 40t cell pack vs P42a, or older and newer P42a.

I watched on a smart tv, did not yet see comments.

Interesting that Dewalt and Ridgid are using JP40’s too in their newest packs.

Those bosch series strips looked pretty thin.

[Evwan]

@SternWake

Ridgid

Fwiw same factory as milfuckee

[SternWake]

TTI right? They make Ryobi too, i think.

I left a pair of Makita drill and driver in California when I moved. Their batteries were shot, and I didn’t have the room in my overloaded rig anyway. Went with Ridgid for the ‘lifetime service agreement’, when I replaced them. Brushed versions though. 2.0ah standard batteries. Got a good deal on a Ridgid angle grinder and 2 4.0 ah batteries. Home despot has pretty good deals on Ridgid batteries occasionally.

I like Ridgid, as they have the low voltage disconnect in the battery, not the tool, like Dewalt and Makita, don’t know about mikwaukee. I used them to power a booster to charge my eskate battery a few times.

I don’t require Tabless cell performance in my cordless tools, but next battery I build is likely to use them.

[dskate]

I have been doing a lot of reading on tabless cells and am a little spun. Between the Ampace JP40 and the EVE 40PL what’s the general consensus on which is better for a high amperage output pack? Id be looking to build a 12S7P of it with the goal of providing 400A output.

I can find them for within $30 of each other shipped so pricing isn’t a big difference or concern

[Soflo]

From the tests I’ve seen, the jp40 out performed the eve 40pl

[Flyboy]

JP40 is supposed to have slightly more discharge, 40PL is supposed to have better consistency between cells. Mooch has write-ups on both

[Dinnye]

@Flyboy

JP40 is supposed to have slightly more discharge, 40PL is supposed to have better consistency between cells.

Also worth noting that the worse consistency might come from the rumour that the JP40’s available today could potentially be a lower grade cell. So this could change at any point.

But for now I’d personally give up the very small performance difference and go for the EVE for it’s consistency.

[dskate]

Im leaning toward the EVE also. There’s no world in which I’ll need 160A burst that the JP40 can do.

I wonder if I ever even have pulled 400A total from a pack.

EVE at 70A in a 7p would give me 490A available in burst, plenty for a hobby wing max4 ESC setup.

[Battery_Mooch]

@dskate

There’s no world in which I’ll need 160A burst that the JP40 can do.

That 160A/2sec spec isn”t for the JP40. It’s for the AM04 and there’s no life cycle testing to judge its impact on the cell.

Ampace rated the JP40 at “only” 140A/5sec.
Longer bursts at 60A (if not hot) and continuous at 45A.

[Battery_Mooch]

@Dinnye

But for now I’d personally give up the very small performance difference and go for the EVE for it’s consistency.

I definitely prefer the 40PL right now for its consistency and we may not be giving up much in the way of performance either…more testing to come when a pile of 40PL’s arrive.

[dskate]

Thank you for the clarification

[tech.shit]

Isn’t the “burst” rating essentially irrelevant as the times are all different and we don’t know how long our longest “pulse” might be?

I was under the impression since the vaping days that CDR was the only amp rating worth caring about.

[Battery_Mooch]

Consider it a burst “capability”, one that many cells can do. IMO to make it a rating we need to know how often frequently we can do it and its effect on cycle life.

@tech.shit

Isn’t the “burst” rating essentially irrelevant as the times are all different and we don’t know how long our longest “pulse” might be?

For many applications, yes. But moderate bursts, 5sec perhaps, can be handy for PEV pack acceleration considerations. Different lengths can be applied to different applications that we might not be considering.

But, yea, most of these capabilities are listed merely for marketing purposes IMO.

@tech.shit

I was under the impression since the vaping days that CDR was the only amp rating worth caring about.

For comparing cells, pretty much so. Unless you get equal true burst/pulse ratings you can directly compare.