and i need to know what mah or v is needed of the solar panel so it can charge it .
2006-12-05 16:32:38 · 3 answers · asked by bcbjerke 2 in Science & Mathematics ➔ Engineering
Solar panel voltages start at 12 volts, so even the smallest available solar panel will do it.
You will need to put a resistor in series with the battery and the panel. The resistor rating will depend on how fast you want to charge the battery, and how high a charge rate the battery can stand without getting overheated. Without a sophisticated charge regulating device, it will be necessary to disconnect the charging circuit when the battery is fully charged.
2006-12-05 16:51:12 · answer #1 · answered by Ed 6 · 1⤊ 0⤋
Not a simple question. You need to push a current into the battery but you are working from a source with an output that varies with sunlight. And efficiency matters -- you don't want to lose power while converting the variable solar cell's output to what the battery charger requires. For this, you probably need a high-efficiency DC-to-DC converter that operates from a range of input voltages. Fortunately, they exist as integrated circuits.
Unfortunately, you can't just buy some chip and wire it up -- there is some design work. There are many application notes that will help. See: http://www.maxim-ic.com/appnotes10.cfm/ac_pk/5 for a nice index of many battery charger app notes.
2006-12-05 17:55:17 · answer #2 · answered by Moe 2 · 0⤊ 0⤋
Build Home Solar Power : http://SolarPower.siopu.com/?BrT
2017-04-01 19:36:05 · answer #3 · answered by Elise 3 · 0⤊ 0⤋