Soldering Liquid to connect Lithium batteries

[Daffy D]

For connecting banks of Lithium type batteries that usually need to be spot welded. 

 

 

https://www.lazada.co.th/products/iremax-hwy-800-i2555155538.html?spm=a2o4m.searchlist.list.47.6aa1baeehATMAv

 

Anybody tried this?

Does it work?

 

[OneMoreFarang]

I do it like Bruce. It works just fine.

 

 

[Daffy D]

2 hours ago, OneMoreFarang said:

I do it like Bruce. It works just fine.

 

 

Looks simple enough.

 

I'm thinking of replacing the batteries in my Xiaomi air pump and getting the connections is a bit more complicated than what Bruce did.

 

Guess the principle is the same so should work. 

 

 

[OneMoreFarang]

3 minutes ago, Daffy D said:

Guess the principle is the same so should work.

Make sure you have a soldering iron which has enough power.

I think the important part is that the soldering process does not take long. Heat it, connect it, done.

10s applying heat to the battery is probably not a good idea... 

[steven100]

This is what you need ....

 

or this ....

 

 

[steven100]

48 minutes ago, OneMoreFarang said:

Make sure you have a soldering iron which has enough power.

I think the important part is that the soldering process does not take long. Heat it, connect it, done.

10s applying heat to the battery is probably not a good idea... 

Heat damages the batteries and usually they have large steel end caps that don't like to take solder.

 

The internals of a rechargeable battery are very delicate and can easily be damaged by the heat of a soldering iron.

[OneMoreFarang]

14 minutes ago, steven100 said:

Heat damages the batteries and usually they have large steel end caps that don't like to take solder.

 

The internals of a rechargeable battery are very delicate and can easily be damaged by the heat of a soldering iron.

Tell that to Bruce, see video above.

And in case you don't know him, look him up. He knows what he is doing. 

[sometimewoodworker]

The thing to use is a battery spot welder (no soldering required), they are cheap for the occasional user (฿1,000 ish). provide virtual instant heat for an extremely short time so the batteries do not suffer from the heat a conventional soldering iron uses.
 

It is the same way that a plasma cutter uses 4 x the heat of the sun (25,000C plasma) to cut but the workpiece can be handled almost immediately after. Compared to an angle grinder which takes much longer heats the metal to around 1,000C  and you will get badly burnt if you pick it up immediately without wearing gloves

Edited September 14, 2023 by sometimewoodworker

[Daffy D]

3 hours ago, sometimewoodworker said:

The thing to use is a battery spot welder (no soldering required), they are cheap for the occasional user (฿1,000 ish). provide virtual instant heat for an extremely short time so the batteries do not suffer from the heat a conventional soldering iron uses.

I only need it for this one job.

 

I realise ฿1,000  isn't so much but for that I could buy a new pump and save all the bother of fixing this one.  

[sometimewoodworker]

13 minutes ago, Daffy D said:

I only need it for this one job.

 

I realise ฿1,000  isn't so much but for that I could buy a new pump and save all the bother of fixing this one.  

This being Thailand, if you know were to go and who to ask and can speak Thai you can get it done for 200 Baht or so.

[Crossy]

5 hours ago, sometimewoodworker said:

This being Thailand, if you know were to go and who to ask and can speak Thai you can get it done for 200 Baht or so.

 

Many branches of Amorn (which sell the batteries) also offer the spot-welding service.

[Daffy D]

In my neck of rural land there aren't many if any repair guys for this kind of small stuff.

 

The nearest Amorn shop is Saraburi but it's only a small place and doesn't seem any sort of workshop area. They might have something out the back, or perhaps can send it away. Next time I'm in town will ask them.

 

Seems odd that, considering how complicated battery replacement is on this thing, that they don't sell spare battery packs.

 

Well anyway I can't find any 

 

[sometimewoodworker]

1 hour ago, Daffy D said:

The nearest Amorn shop is Saraburi but it's only a small place and doesn't seem any sort of workshop area.

Battery spot welding doesn’t need a workshop, you can do it with a power bank and a very small area, less than 10cm x 10cm is sufficient unless you have a large number of cells, that doesn’t need to be protected from heat, so while your Amorn may not offer the service it’s a choice not a space problem.

[Daffy D]

1 hour ago, sometimewoodworker said:

Battery spot welding doesn’t need a workshop, you can do it with a power bank and a very small area, less than 10cm x 10cm is sufficient unless you have a large number of cells, that doesn’t need to be protected from heat, so while your Amorn may not offer the service it’s a choice not a space problem.

What I meant was that Amorn did not seem to have area for repairs in the shop.

 

Last time I was there I wasn't looking to repair anything so may have missed it. 

 

[sometimewoodworker]

7 hours ago, Daffy D said:

What I meant was that Amorn did not seem to have area for repairs in the shop.

 

Last time I was there I wasn't looking to repair anything so may have missed it. 

 

I realised your meaning, you probably overestimate the equipment and space needed to spot weld batteries like the 18650 

here s a video showing how to use it 

here is a battery powered unit that takes virtually no space