Sol Republic Punk Preparing a new battery for Replacement

Here is the original battery for the Sol Punk. The battery is a 18490 Li_ion 5.18Wh 1400mAh 3.7V

The battery control board is connected to the battery via two nickel strips. The Blue arrow shows the negative (-) and the Red arrow the positive (+) connection

First thing to do is to desolder those connections.

Desoldering thos strips is easy enough and one can see they are strictly just bend over to form a solder tab.

Do the same for the other tab

Both contacts have been desolder and battery control board is now off the battery

Since the 18490 battery seems to be scarce, I opted for the 18500 model. It has identical electrical specs then the 18490 but is readily available.

18490 length is 48.9 mm and the diameter is 18.04 mm

The 18500 is 48.9mm in length

but it is 18.10 mm in diameter. The difference will not interfere in the Sol Punk. There is room to accommodate that size

The nickel strips used on the old battery are ~3 mm in width.

The only strips available at this time are 4 mm strips

Checking to see if the 4mm strip will fit. There is enough room on the solder pads of the battery control board, to accommodate that size strip.

Clean the contact side of the battery in preparation for the weld of the strip

and clean the strip itself as well

Here is the spot welder being used and it's settings are indicated by the blue LED's

Lay teh nickel strip straight on the battery contact and use the spot welder according to its instructions. This one does not have a trigger and will weld when it senses contact with both post.

Nickel strip solidly attached. The miss on the top is related to not wearing eyeglass when needed :-)

Bottom or Negative Strip welded to battery. Use the battery control board to ensure the direction of the Top or Positive Strip.

Spot weld the Top or Positive strip the same way as prior done with the negative. Place the strip at a 180 degree from the negative

Now bend the Bottom or Negative strip up while having it tight to the body of the battery. Use something like a rubber band, or zip tie etc to ensure it is close to the body.

Place the battery controller on the top and measure the Negative strip. Bend it and cut it so it covers the solder pad. Do the same for the Positive strip

Then solder both tabs to the battery control board in conventional manner.

After soldering clean the flux with a cotton tip applicator and some isopropyl alcohol

Here is the new battery ready for installation