D cell dilemma
mcgivor
Solar Expert Posts: 3,817 ✭✭✭✭✭✭
My high power Led flashlight uses 3 D cells, unfortunately the commonly available $0.60 Zinc Carbon cells don't last very long, alkaline ones such as Duracell are expensive in Thailand at $3 each and are marginally better. The rechargeable NiMh or NiCad type don't perform well due to the nominal 1.2v, a loss of 0.9V, this got me thinking about lithium but the cell voltage is too high, but if I was thinking along those lines then others must have done so as well, so I researched and they do exist so I ordered some to evaluate.
Unfortunately they mistakenly sent C type and due to Covid restrictions at the time, I was unable to return them so I simply made an adapter, they are excellent, the light output is constant, as soon as it drops, which is sudden, it's time to recharge. The disposable type gradually drop over time so usually disposed before end of life due to the high demand. The cost was a $26 for 3 so a little over double the Duracell price they last longer and after 3 recharge cycles they will have paid for themselves.
Unfortunately they mistakenly sent C type and due to Covid restrictions at the time, I was unable to return them so I simply made an adapter, they are excellent, the light output is constant, as soon as it drops, which is sudden, it's time to recharge. The disposable type gradually drop over time so usually disposed before end of life due to the high demand. The cost was a $26 for 3 so a little over double the Duracell price they last longer and after 3 recharge cycles they will have paid for themselves.
1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Comments
Not sure what/how these are 1.5 volt lithium rechargeable, but the native lithium cells would be 3.2-3.7 volts, so something 'extra' is going on...
- Assorted other systems, pieces and to many panels in the closet to not do more projects.
Obviously there is internal voltage reducing circuitry involved to output 1.5V from the lithium cells but so far they have outlasted a set of alkaline cells and probably 3 sets of cheap zinc carbon type. Can't say one way or another how they would work with other loads but would think there would be little difference, one time disposable cells are dinosaurs, just trying to extend the useful life of my trusty workhorse flashlight/weapon.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.