[Battery Buyer]

I want to test this cell to see how it compares to whatever cell I've been calling 'EHW5'.

It's not "whatever cell you've been calling" an EHW5 lol... it's a Panasonic cell, basically a newer version of the Cmax 5Ah cell in a clear wrapper. Out of the 100s of them I have tested, my best ones are right at 5.5ah, with most being in the 5.3xx range when in good health.

One thing I definitely left out is, the Panasonic LiMn4O2 cells are 3.7 nominal voltage, while the Blue Energy Li(NiCoMn)O2 cells are 3.6. Not a huge difference, just another difference.

 

[mudder]

I'm sure you've already mentioned this cell's part number... and I just haven't found it. Can you tell me the part number, so I can stop using 'EHW5' (and replace it with the actual part number).

 

[joeaax1j]

I'm trying to follow the latest in this thread, but am getting confused. Are we saying that my 48S LiBCM which I installed back in February/March, with what I understood to be an EHW5 18S+, and an EHW5 18S-, and a converted EHW5 18S+ to a 12S+ is not actually EHW5, after all?

 

[Battery Buyer]

I'm trying to follow the latest in this thread, but am getting confused. Are we saying that my 48S LiBCM which I installed back in February/March, with what I understood to be an EHW5 18S+, and an EHW5 18S-, and a converted EHW5 18S+ to a 12S+ is not actually EHW5, after all?

No clue what you have, but the easiest way for me to answer your question is... If your cells are blue and welded, they are EHW5 cells. If they are silver and bolted, they are Panasonic Insight cells.

I have no idea what this might change in the project you guys have going on here, if anything, but I just wanted to clarify which cells you guys are using so that you can actually buy what you are looking for. If you set out in search of 12s silver bolted modules, and are asking for EHW5s, you aren't gonna find any. Or will receive the wrong thing.

 

[Recovering_Gasaholic]

I'm trying to follow the latest in this thread, but am getting confused. Are we saying that my 48S LiBCM which I installed back in February/March, with what I understood to be an EHW5 18S+, and an EHW5 18S-, and a converted EHW5 18S+ to a 12S+ is not actually EHW5, after all?

Yes, it's close to EHW5 but a cell made by Panasonic. It should still be pretty good, I believe Panasonic makes batteries for Tesla.

 

[mudder]

Are we saying that my 48S LiBCM which I installed back in February/March, with what I understood to be an EHW5 18S+, and an EHW5 18S-, and a converted EHW5 18S+ to a 12S+ is not actually EHW5, after all?

That appears to be the case. I agree it's been a confusing discovery process, but yes it appears we are just using "Panasonic Insight" cells.

No clue what you have, but the easiest way for me to answer your question is... If your cells are blue and welded, they are EHW5 cells. If they are silver and bolted, they are Panasonic Insight cells.

We're using Panasonic Insight cells.

I have no idea what this might change in the project you guys have going on here, if anything, but I just wanted to clarify which cells you guys are using so that you can actually buy what you are looking for. If you set out in search of 12s silver bolted modules, and are asking for EHW5s, you aren't gonna find any. Or will receive the wrong thing.

This doesn't change any technical component of the project... it just means we've been calling a hammer a screwdriver... so we have Panasonic Insight cells, not EHW5 cells. It's two blind men describing an elephant.

@Battery Buyer has mentioned that the Panasonic Insight cells don't last as long from a cycle count perspective, but in the G1 Insight application that doesn't matter: cell aging will kill these cells long before cycle count does. So as far as the G1 LiBCM conversion is concerned, there is almost zero difference between the two cell types.

Obviously I have a lot to update over on the main project page. Not sure I'm going to take the time to retroactively change every instance of EHW5 here on ic.net, but certainly I'll add a note to the most important pages that reference EHW5.

 

[eprom]

I ordered several samsung fomoco 47Ah batteries, one of them was damaged.
I contacted Batteryhookup and they sent me another battery to replace it.
I just noticed that the replacement battery I received last week is not the same model as the others.

The first ones I had were LX68-10C790-G-PIA-3AB
the last one I received is an LX68-10C767-F and it's written 49.5AH
Both batteries look identical, same number of cells, the only difference I noticed is the black plastic cover which is glossy and not textured.
I checked and it's the same circuit inside

Can I mix the two battery models and connect them in series ?

 

[mudder]

These "close-but-not-the-same" module variants are super annoying!

Ideally all the modules in a particular pack are the same.

From a safety standpoint, the LiBCM firmware is far enough along that it won't overcharge/overdischarge mixed cell packs, as long as all cell types can handle being operated between CELL_VMAX_REGEN and CELL_VMIN_ASSIST.

Beyond that, though, the LiBCM firmware isn't far enough along that I can recommend mixing cell types. So while it's 'safe' to operate mixed cell packs, I don't recommend it. If you do decide to run different cell types in the same pack, you'll need to set STACK_mAh_NOM to the LOWEST nominal cell capacity.

In your specific case, the cells are probably the same chemistry and are about the same size... so as long as you change STACK_mAh_NOM to 47000 (and not 49500) it should probably work just fine.

In a couple months the firmware will support "per-cell SoC and SoH", at which point we can revisit this topic. For now my blanket statement is "don't mix different cell types".

...

FYI: The QTY5 modules I have are all LX68-10C790, 2.07 kWh. That's what I will focus my efforts on. I must limit my focus, as there are many more cell chemistries out there than I have hours to characterize them. All of these tangents are fun to think about, but right now they're preventing me from focusing on core firmware development.