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[EVDL] charging a 48V pack with a 36V charger?

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Project ForkenSwift currently has 2 chargers available for its 48V pack:

- a 36V 20A taper charger with a manually set timer and an ammeter;
- a 24V 5A taper charger with an automatic voltage-sensing shutoff timer
(which sometimes doesn't shut off because the old batteries don't quite
reach the programmed voltage threshold).

I'd like to use the 20A 36V unit, mainly because it's faster. But the
problem is that according to my extensive calculations, 48 can't be evenly
divided by 36.

I was thinking of splitting the car's pack into 24V strings, then adding as
"placeholders" two old floodies (left over floor sweeper batts the forklift
co. gave us) to make up temporary 36v strings that can be individually
charged. These two same "placeholder" batteries will be repeatedly cooked
whenever each half of the car's pack is charged. Will this approach
negatively affect the "good" batteries?

One potential effect I see is the charging current may taper down sooner
because those placeholder batts will have more resistance than the four good
batts. Is that a serious problem?

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