DiY

Photo post: can’t afford a battery pack, so hand-build one — 15 brand-new 18650 1500mAh 10C power cells + BMS, AWithZ spot welder ‘the ceiling of spot welders’, bright and full weld spots; comment ‘the ceiling? what does that make Miyachi’, creator backpedals: ‘it’s a small spot welder’

12-image tutorial: can’t afford a battery pack, what to do — hand-build one; the BMS (blue) mounts on the cell holder; AWithZ spot welder, ‘the ceiling of spot welders’, ‘the spot welder feels so good to use’; bright, full weld spots; 15 brand-new cells (18650 1500mAh 3.7V), 10C-discharge power cells. 228 comments: ‘the ceiling? what does that make Miyachi’ (creator: haha), ‘if yours is the ceiling, what does that make mine’ (creator: it’s a small spot welder); an IR meter, a spot welder and a balancer will set you back plenty, fine to play with but don’t get serious; buying one is usually cheaper than building (creator: plenty of fake cells too); no welder, just copper wire (creator: that works); ‘it’s not that you can’t afford a pack, those who know, know’ (creator: 10 cells, 5 cells of sand).

Outcome

Steps6 steps · click a frame to jump

1. 
   1. Can’t afford a pack → hand-build; BMS onto the holder

   Blue BMS mounted on the black cell holder, already wired.

2. 
   2. AWithZ spot welder, ‘the ceiling of spot welders’

   Black AWithZ colour-screen unit, red welding-pen leads.

3. 
   3. The spot welder feels so good to use

   Spot-welding nickel strip on the positive side of the cells.

4. 
   4. Bright, full weld spots

   Weld spots across the whole nickel strip face.

5. 
   5. Using 15 brand-new cells

   Pack made of 15 green 18650s.

6. 
   6. 10C-discharge power cells

   Cell label 18650 1500mAh 3.7V.

Bill of materials

Pitfalls

• Comments: buying one is cheaper than building; IR meter, spot welder and balancer are a big outlay, fine to play with but don’t get serious

Li-ion safety

Quotes