possible solar top-up charging of two nimh in series

circuit-20260306-0313.svg

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stroke-dasharray=""/></g><path fill="none" stroke="#807f7f" paint-order="fill stroke markers" d=" M 1232 480 L 1232 452" stroke-linecap="round" stroke-miterlimit="10" stroke-width="3" stroke-dasharray=""/><path fill="none" stroke="#807f7f" paint-order="fill stroke markers" d=" M 1220 452 L 1244 452" stroke-linecap="round" stroke-miterlimit="10" stroke-width="3" stroke-dasharray=""/><path fill="none" stroke="#54ab54" paint-order="fill stroke markers" d=" M 1232 416 L 1232 444" stroke-linecap="round" stroke-miterlimit="10" stroke-width="3" stroke-dasharray=""/><path fill="none" stroke="#54ab54" paint-order="fill stroke markers" d=" M 1220 444 L 1244 444" stroke-linecap="round" stroke-miterlimit="10" stroke-width="3" stroke-dasharray=""/><text fill="#ffffff" stroke="none" font-family="sans-serif" font-size="12px" font-style="normal" font-weight="normal" text-decoration="normal" x="1246" y="454" text-anchor="start" dominant-baseline="alphabetic">100μF</text><path fill="none" 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sim

after charged:

Use 3v zener for more precise voltage:

sim

maybe that 1k resistor on the right isn't necessary or could be much smaller.