The battery builders club

How-Tos & Esk8 mechanics
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#9321

It’s an Hobbywing ESC in his board
This basically means any cell better that the 35E will be ok?

#9322

Honestly I think the hobbywing is like 24A battery. But I would assume 30A. So as long as the 10S2P or 3P pumps out more than that you should be good to go.

1 Like
#9323

Thanks a bunch

1 Like
#9324

I’ve never handled a truly puffy lipo or one beginning to puff… Can someone tell me how it should feel if I feel like a battery is starting to puff?

This one used to be just a solid rectangular brick, and now it feels like a tiny bit of air got underneath the shrink wrap. Whatever deformation just feels like nothing as if it’s still a perfectly rectangular brick by the feel of it, but just looks like 2% less square.

Is this the start of puffing? When it puffs will the puffed lipo be hard, or soft like the softest pillow?

#9325

That is the start of puff. Going full puff takes some time, it should be squishy like an orange. If it gets hard and puffy that’s too much pressure and you should really hook up a lightbulb outside and drain it to 0v for disposal.

Discharge ability and capacity degrade pretty quick. Worst I’ve seen is a 12000mah 6s pack I have that seems to do about 7000-8000mah now. It’s pretty puffy, but still works for testing esc’s and just lives at 3.8v/cell now. I don’t fully charge it ever.

1 Like
#9326

You should try tearing it off with pliers to be sure, but looks good to me! :slight_smile:

(Kinda surprised the nickel doesn’t even look bent, would be funny if you actually just punched holes in it)

1 Like
#9327

Is there the same risk with lifepo batteries for shorting over the shoulder like with li-ions? The reason I ask is because I noticed on these A123’s, the - and + terminals look opposite of on a liion battery. See below:

15966543324272516463482562320640
159665433242725164634825623206403024×4032 2.06 MB

The negative terminal is insulated just lile, and looks just like, the positive terminal on a liion battery. This makes me wonder about the construction of the batteries, and how similar and different they are of liion batteries. Is the majority of the battery negative, like a liion battery, or is it the other way around for lifepo batteries? And if depending on whether that’s the case, is there still the risk of shorting over the shoulder with something like this? (See below image)
15966545223036196405668751014376
159665452230361964056687510143763024×4032 1.94 MB

I haven’t seen people rewrapping these cells on the forum before so it makes me question whether I need to do that and add terminal rings to these cells. Ehh? Any words of knowledge on this subject?

1 Like
#9328

What’s up guys. I have a pretty old 10s4p VTC6 pack. After a full charge all groups but one are 4.17V when charger stops. The one high group is 4.20V. The whole pack is 41.5 when the charger stops. Thoughts? Do I have a bomb on my hands?

#9329

There’s a slight bend into the positive terminal, I just zoomed in on a shitty photo so it’s hard to tell :sweat_smile:

Just a little confused as to why my left side welds are a little bit more burned than the right side but overall, pretty happy with my hand welds

#9330

Just has to deal with the pressure you apply and how clean / uniform the tips are. Not too big of an issue imho.

1 Like
#9331

They’re opposite of 18650s, the whole outside is positive and the small ring is negative. The same rules apply, so I would buy terminal rings. The large flat side is super thin, so you gotta be careful when welding too.

Believe me with the max of 70 amps out you don’t want to have these short even for a second

2 Likes
#9332

So that being said, with such high discharge do you think it unwise to use .15mm nickel?

Also @ShutterShock did you order any wraps or rings for these? Was wondering if you could help a brotha out if you have some :sweat_smile:

#9333

I’d aim for something a little beefier than that if possible

Also anything over 41mm flat width I think is right

#9334

Uhh where TF do I find nickel that’s 41mm wide and thicker than .15mm…I wanted to use my 25.5 X .15mm ladder nickel because I have tons of it

#9335

Oh sorry that is for the shrink wrap

For the nickel some 20x0.2 should do it, but you need more welds (each is 5A)

#9336

Lol I was like wtf bruh WHERE??

I have tons of clear 18650 wrap if any one wants to trade for some 26650 wraps. I only need 15 of em. And you’ll get however many is in this stack:

15966561241725940289121806290420
159665612417259402891218062904203024×4032 2.49 MB

1 Like
#9337

You want some 60mm flat black? I will try to send the magnets for the 3rd fucking time and I can add some

1 Like
#9338

Think it’ll shrink enough to squeeze a 26650?

#9339

It’s rated for 40% shrink so it should

1 Like
#9340

Don’t throw those cursed magnets in, it’ll never make it here!! :rofl:
Just kidding, you should for SCIENCE sake! Yeah let’s do that. Send me 20 wraps if possible, I’ll send these to ya. And dont forget the key plz! :pray: