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OT: Soldering large 18650/20700 lithium-ion batteries?

Started by John Doe January 5, 2020
On 2020-01-05, John Doe <always.look@message.header> wrote:
> I am neat, careful, and quick to avoid overheating when soldering. How > possible is it to solder a large lithium-ion battery without damaging or > degrading the battery? For connecting batteries together.
> I like doing things right, so I'm willing to buy a $100 Chinese battery > connector welding box. But the foreseeable need is only about five two- > cell battery packs. You do the math...
can you rent, or borrow one, or contract out the spot welding? or perhaps build one from a MOT. -- Jasen.
John Doe <always.look@message.header> wrote in
news:qutmui$lmi$1@dont-email.me: 

> I am neat, careful, and quick to avoid overheating when soldering. > How possible is it to solder a large lithium-ion battery without > damaging or degrading the battery? For connecting batteries > together. > > I like doing things right, so I'm willing to buy a $100 Chinese > battery connector welding box. But the foreseeable need is only > about five two- cell battery packs. You do the math... > > Thanks. > > > >
Gold foil tabs and compressive contact in a tight fitting enclosure. Tiny spot welder. Braze, but that soaks way more heat, but you would then find out with that one battery just how much damage heat causes, if any. Solder takes so long to get a good "wetting" that it likely soaks more heat than brazing would. If there is a such thing as a small diameter wire welder (MIG), then you might find a setting that would let you "spot weld" with it. You would need a single spot. One heat test would be to attach wires to a single battery and place it in a thermal chamber and observe its behavior through a moderate load as the temperature climbs. Then you could tell if a single high heat attachment event is particularly damaging or not. Or do it outside the box by using a chef's torch to heat an end up and check for degradation.
John Robertson <spam@flippers.com> wrote in
news:f7KdnWXed6uz84_DnZ2dnUU7-SednZ2d@giganews.com: 

> On 2020/01/05 2:34 p.m., edward.ming.lee@gmail.com wrote: >>> Folks have had success using a car battery for spot >>> welding...Use the >> starter solenoid and a push button and heavy copper lugs for the >> welding points. >> >> You can also use battery packs itself to spot weld additional >> one. Start with some spring mounted cells, than build it up. >> >> I am testing my 2 Kw 18650 packs on my Leaf now. Went a little >> farter > > Gas powered, eh? > > (sorry, couldn't resist). > > John ;-#)# >
That joke stinks!
edward.ming.lee@gmail.com wrote in
news:8fe744ab-5eef-461c-a608-15a6b81c0df6@googlegroups.com: 

> Folks have had success using a car battery for spot welding...Use > the >> starter solenoid and a push button and heavy copper lugs for the >> welding points. >> >> You can also use battery packs itself to spot weld additional >> one. Start with some spring mounted cells, than build it up. >> >> I am testing my 2 Kw 18650 packs on my Leaf now. Went a little >> farter > >> Gas powered, eh? > > Sorry, no gas, went further than before. >
You must have missed the joke. Look at your spelling.
On 1/5/20 10:39 PM, DecadentLinuxUserNumeroUno@decadence.org wrote:
> edward.ming.lee@gmail.com wrote in > news:8fe744ab-5eef-461c-a608-15a6b81c0df6@googlegroups.com: > >> Folks have had success using a car battery for spot welding...Use >> the >>> starter solenoid and a push button and heavy copper lugs for the >>> welding points. >>> >>> You can also use battery packs itself to spot weld additional >>> one. Start with some spring mounted cells, than build it up. >>> >>> I am testing my 2 Kw 18650 packs on my Leaf now. Went a little >>> farter >> >>> Gas powered, eh? >> >> Sorry, no gas, went further than before. >> > You must have missed the joke. Look at your spelling. >
So, I guess that would be a "Leaf Blower" :-)
On Sunday, January 5, 2020 at 2:11:36 PM UTC-8, John Doe wrote:
> I am neat, careful, and quick to avoid overheating when soldering. How > possible is it to solder a large lithium-ion battery without damaging or > degrading the battery? For connecting batteries together.
If you don't use welding, a solder joint to nickel (or nickel-plated) battery terminals can be made with an overly hot iron, a bit of wire solder, and an acid (HCl/H2SO4) flux. Once tinned, solder at normal solder temperatures (but you wnat to get the surface wet FAST before the battery takes damage, and a cool iron won't do it).
whit3rd <whit3rd@gmail.com> wrote:

> On Sunday, January 5, 2020 at 2:11:36 PM UTC-8, John Doe wrote: >> I am neat, careful, and quick to avoid overheating when soldering. How >> possible is it to solder a large lithium-ion battery without damaging >> or degrading the battery? For connecting batteries together.
> If you don't use welding, a solder joint to nickel (or nickel-plated) > battery terminals can be made with an overly hot iron, a bit of wire > solder, and an acid (HCl/H2SO4) flux. Once tinned, solder at normal > solder temperatures (but you wnat to get the surface wet FAST before > the battery takes damage, and a cool iron won't do it).
Spot welding is probably safer and more reliable. There are tons of examples on Youtube and on the web: CHEAP Spot Welder DIY (using simple tools) PLANS https://www.youtube.com/watch?v=4q4oMVtW4FI How To Make Mini Spot Welder Using old Microwave Transformer https://www.youtube.com/watch?v=4qf559CgmK0 Battery Spot Welder (CD Welder) || DIY or Buy https://www.youtube.com/watch?v=5TVNdMqVZpk DIY Spot Welder https://www.youtube.com/watch?v=65I4Zx5VDKo Making a simple Spot Welder https://www.youtube.com/watch?v=76tuG4ESJbA DIY How to make a home use spot welder with a car battery https://www.youtube.com/watch?v=8bxBGA0L8NQ Making a Regulated Spot Welder for Batteries https://www.youtube.com/watch?v=bpYyEgpIo2k DIY Arduino Spot Welder V3 https://www.youtube.com/watch?v=CNmvx2JSCvA Testing out an Arduino SPOT WELDER https://www.youtube.com/watch?v=e9mnTABWSpo DIY Spot Welding Machine https://www.youtube.com/watch?v=hTaGa93lOGU DIY Arduino Spot Welder V3 Software Update https://www.youtube.com/watch?v=m_vmw5Daf0I DIY Spot Welder, Attempt #2 with Microwave Transformer, Failed https://www.youtube.com/watch?v=MU1f2HS0jLY DIY Battery Spot Welder - Demonstration & Explanation https://www.youtube.com/watch?v=o1NFbchHeM8 Making a spot welder from microwave oven https://www.youtube.com/watch?v=qdAichAdBVs Spot Welding Machine https://www.youtube.com/watch?v=qdnTU10z4Xc Malectrics Diy Arduino Spot Welder https://www.youtube.com/watch?v=ReY7bz3tsMM Make your own spot welder with foot pedal https://www.youtube.com/watch?v=VqVYsqGJNMs How to make a DIY Spot Welder free - 18650 spot welder- PART #1 https://www.youtube.com/watch?v=zmss5t0idrs
So where are you getting 20700 batteries?  Tesla makes 21700, are you buying used model 3 batteries? 

-- 

  Rick C.

  -- Get 1,000 miles of free Supercharging
  -- Tesla referral code - https://ts.la/richard11209
> So, I guess that would be a "Leaf Blower" :-)
Yes, that's the secret plan: SRB motors on my Leaf Blower. Wondering if I need a permit to test at Edward's AFB.
Bill Martin <wwm@wwmartin.net> wrote in news:qv0tpf$r01$1@dont-
email.me:

> On 1/5/20 10:39 PM, DecadentLinuxUserNumeroUno@decadence.org wrote: >> edward.ming.lee@gmail.com wrote in >> news:8fe744ab-5eef-461c-a608-15a6b81c0df6@googlegroups.com: >> >>> Folks have had success using a car battery for spot welding...Use >>> the >>>> starter solenoid and a push button and heavy copper lugs for the >>>> welding points. >>>> >>>> You can also use battery packs itself to spot weld additional >>>> one. Start with some spring mounted cells, than build it up. >>>> >>>> I am testing my 2 Kw 18650 packs on my Leaf now. Went a little >>>> farter >>> >>>> Gas powered, eh? >>> >>> Sorry, no gas, went further than before. >>> >> You must have missed the joke. Look at your spelling. >> > So, I guess that would be a "Leaf Blower" :-) >
I wonder if that option was available on Fred Flintstone's car. Gota think of a make model name. Like in Robocop... The SUX9000! Own a piece of a rock! The foot blister 3000. The StoneHenge. Definitely heavier than a Leaf. Hey I know... Cheops! The Asteroid!