Sir whiteoutage . . . . . . . . .
( No power outages HERE . . . . . .at least . . . . . not yet! )
Are Your
WEED EATER branded battery packs being the smaller Black and Green WE20VRB 20V Lithium-Ion or the heftier / larger Black and Gray B16-2025, 20V Battery ?
Can you check the battery case and see if its 2 clam shells typical 4 retaining screws are something that you can handle. OR is it using sets of . . .
SPECIAL TORX screws with the ADDITIONAL small SECURITY hole in the center ?
I have a full set of same, although, years/decades back, on my day-one encounter . . . I defeated them by using a hacksaw blade ground down with a Dremel cut off wheel to a just snug fit between two cross splines to get them broke loose and started out, then there was one of a standard jewelry screwdriver set, that fit in the same manner and then let me get them fully out.
Then I . . . .Dremel cut . . . . a slot across their ends to then make them standard slotted screws.
BECAUSE . . . . . you will need access to the packs individual cells.
2.5 V per cell is dropout voltage threshold detection / acceptance for a charger designed for LI - ION type cells CC charging, but it appears that some of yours are partially trying to respond to your charging effort.
Parts wise, do you have either an LM317 I.C. . . . . ./ or discrete components . . . . ./ as a plastic TO-220 or TO-3 NPN power transistor . . . . or tell us what variants thereof, you might have .
Also a PNP small signal silicon transistor and a 1/2 w 1.5K resistor and another resistor in the 22-47 ohm range . . .tell those values available, also.
Can / Do you sort of sarter . . . . . (solder) . . . .and micro build / breadboard / lashup ? (4 components)
73's de Edd . . . . .
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