PINNED - Lithium battery conversion/info

[Burgerman]

You will lose around 15% range at full speed, and about 40% more current (taking quite large chunks at high amps) accelerating at low speeds and while hill or slope climbing.

On my PC your photo is inverted!

>>> Not me. I'm in USA.

[shirley_hkg]

Found ONE bad cell , amongst 400 , bought and set aside last year .

Voltage 3.317V still .

[Burgerman]

Looks like it is deseased!
Did you test capacity? At say half C rate to 2.5V you should get full capacity.

[snaker]

I just finished discharging the pack from full to empty (2.90V). The total Ah taken out is 47+91.7 = 138.7Ah. Cell 6 appears weaker than the rest. Can I do anything to improve its voltage?

After discharging 0-47Ah

After discharging 47-138.7Ah

Cell volts at the end

[shirley_hkg]

I'd swap ONE cell of group 6 & 4 , with that of the 7 & 1 respectively .

Existing state is fine already .

[expresso]

I would think that since you have 150ah - thats large - you may never get low enough in a day to be too concerned - unless Cell 6 gets worse - Cell 2 and 3 are the next which are in the 3v area after Cell 6 -

i have 135ah now - and i havnt been able to get past 44 Miles at the most so far - used up about 100ah - leaving 35ah still - maybe BM may have a solution to condition it a bit - maybe a tweak with the charging preset to help it a bit -

[expresso]

I'd swap ONE cell of group 6 & 4 , with that of the 7 & 1 respectively .

Existing state is fine already .

i see - that makes good sense - would even it out and discharge more evenly - nice - pain that you have to take it apart but with those big cells - its easier than using the Headways

[snaker]

Yes, reassembling cells is truly a pain. If the cell 6 is not a big problem, I will leave it alone.

[Burgerman]

Would definitely watch 6. Theres one slightly bad cell there.

[dEknowmight]

Odd about that photo.. makes Australia sounds funny now.

[Burgerman]

Does anyone else see it upside down?

[expresso]

Does anyone else see it upside down?

yes - i see it - its down under - upside down

[Gnomatic]

Does anyone else see it upside down?

That pic shows as upside down for me as well, in Chrome, Firefox, and IE. So its not a browser thing.

[Burgerman]

Must be because australia.

[rustyjames]

It's upside down for me too, but it wasn't yesterday.

[Gnomatic]

Dang. These can be had for ~$13/unit now.

https://item.taobao.com/item.htm?spm=a2 ... =14#detail

Wouldn't mind ordering about 20 cells(using the 16 strongest) and basically make a clone of snaker's pack. At that price its seems worth it to take a flyer on these. Winter project for second chair. But getting them shipped to the US is .

[expresso]

that would be great price wise - and 150ah would be very nice to have on hand - inside a chair - thats amazing -

[Burgerman]

Remember that the casings are all 3.3v apart. And he got 135Ah out. And a faulty looking cell. So not ideal.

[Gnomatic]

That's why I'd get 20, a 25% bad/weak cell allowance. Theres room for ample insulation in between each cell in both my chairs. So maybe not ideal, but at that price, hard to complain.

[Burgerman]

It's upside down for me too, but it wasn't yesterday.

How can that be possible

If I download it, save to desktop it displays the right way up in paint shop pro! And presumably photoshop. Try it!

[Burgerman]

And uploaded it again. In windows its correct. In photoshop its correct. When uploaded its upside down to me here. What gives.

[snaker]

That's why I'd get 20, a 25% bad/weak cell allowance. Theres room for ample insulation in between each cell in both my chairs. So maybe not ideal, but at that price, hard to complain.

These cells are not that bad. You do not need 4 spare cells but because they are so cheap, 4 spare cells are not a bad idea. I note that I left their metal cases which are also positive poles touch the ground in 2 weeks. They should be all dead but they survived (although with weak health ). I would not have faced any problem if they had been insulated and stored by the right way.

My worried thing is the naked metal case. It is so dangerous. It would be better if you could find other cells with plastic cases for the same or a little higher price. Shirley might help

[rustyjames]

It's upside down for me too, but it wasn't yesterday.

How can that be possible

If I download it, save to desktop it displays the right way up in paint shop pro! And presumably photoshop. Try it!

I have no idea, all I can tell you is that when I first saw it it wasn't upside down

[snaker]

The pack's charging graphs do not look perfect but seem Ok. I see in the IR graph, cell 6's IR is lowest. In theory, it should be stronger than other. Why is it weaker in reality?

[expresso]

if you click on the picture - it shows up correct - its upside down just on here

[rustyjames]

Forgot to mention, cool Dog!

[dEknowmight]

The dog is Julie. She loves riding on my lap, and even demands to sit there while I work some days.

I googled a bit on the image and best I can see is that the orientation tags are not honored. iPhone has weird issue sometimes with pics going sideways.. they have to be edited to correct them. Maybe this is related.

[Burgerman]

So another reason not to use betamax.

[snaker]

The pack is ready for the first ride test.

[Burgerman]

Dont come back till its down to 3Vper cell and take food, drink, clothes, and a calender toilet roll . You might be able to leave the country.