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Drill battery fettling/improvements

More-idiot-proof drill-battery charging, and upgrading poorly drill packs

Wookey has built proof-of-concept idiot-proof 1hr charger out of makita charger case and B4 35W autocharger They are £9 each. Donor charger bodies off ebay are about £10-13.

B6 50W charger (£11) would charge faster, but is discontinued.

Tasks

  • Test drill batts from 2017. Done (3 need new cells)
  • Build 2 or 3 balancing autochargers. Cannot source female batt connector, so must buy dead makita chargers (about £10 each). 2 more base bodies bought (May 10th) so we have 3 now. Construction has started. 2nd and 3rd B4s have been ordered. 1st charger built (but not working any more - grrr!)
  • Replace PCBs in 7 ('non-makita-charger') packs with own balance-connector board (about 3 hours per batt!): 2 done (April 15)
  • Rebuild 3 new packs. Needs proper tab-welder (Tried soldering last year, and DIY tab-welding - not reliable enough).
  • Have bought/acquired parts for battery-tab spot welder (1kW transformer, controller, electrodes). Needs assembling.
  • The 2 new packs will need balance-connector board.

Batts

Existing packs mostly use Sony SEUS18650V cells (nominally 1500mAh, 10A) 4Ah pack uses LG DAHD21865 (nominally 2000mAh 25A)

Batt drilling current tested at 26A, so 15A cells needed. UK supplier is https://18650.uk/ Can now get 2 and 2.5Ah 15A cells, so should be able to build 4 or 5Ah capacity packs for ~£40. Nickel tab-strip bought.

Possible 18650 choices: http://18650.uk/ is good source

  • Samsung 25R 2500mAh 20A
  • Samsung 30A 3000mAh 15-30A
  • LG HB2 1500mAh 30A £3.79
  • LG HB4 1500mAh 30A £4.19
  • LG HB6 1500mAh 30A
  • LG HD2 2000mAh 25A
  • LG HE4 2500mAh 20A
  • LG HG2 3000mAh 20A £5.45
  • Sony VTC5A 2500mAh 25-35A £6.19
  • Sony VTC6 £5.45 3000mAh 15-30A £5.45


Last update 2018.05.15