My first solar project.
My neighbor gave me eight 12v12ah batteries for free . He sells used kids riding toys batteries on ebay. These are batteries from a major retail chain store customers returning the riding toys soon after buying them. The toys are crushed and the batteries recovered to sell used. These batteries had cracked handles and were not sellable. The actual battery case is not cracked. The batteries are relatively new. Kid Trax 12v12ah.
I am building a small portable setup for charging tablets and electronics (AA batteries) while camping and power failure situations. I was going to base the system on one 29DC battery from Walmart, but since I got these free I figured it would work for a first solar project that I will likely screw up anyway.
I figure my first step is to determine if the batteries are good and can take a load as designed.I numbered the batteries, took initial voltage readings, then charged all the batteries with a 3amp microprocessor controled auto charger.
I am thinking the best way to 'prove' each battery is to put a load on each battery and record voltage reading over a period of time, down to a target voltage.
I soldered wired connectors to to a 120v 150w halogen bulb (tube type for a work light). It barely lights up and the voltage on a battery drops slowly (.01 very 3 seconds or so). I tried soldering a couple 120v75w bulbs for a load but couldnt get solder to stick to light bulb base.
My question is what voltage should I test them down to. I read somewhere that 12.2v is a good target DOD, and a good guide for the lowest dod for healthy batteries. Should I record voltages every 5 minutes down to 12.2v and graph each battery? A sudden fall off in voltage would be an indication the battery is exhausted or has a bad cell, where a gradual decrease over a long period of time should signify a healthy battery?
My neighbor gave me eight 12v12ah batteries for free . He sells used kids riding toys batteries on ebay. These are batteries from a major retail chain store customers returning the riding toys soon after buying them. The toys are crushed and the batteries recovered to sell used. These batteries had cracked handles and were not sellable. The actual battery case is not cracked. The batteries are relatively new. Kid Trax 12v12ah.
I am building a small portable setup for charging tablets and electronics (AA batteries) while camping and power failure situations. I was going to base the system on one 29DC battery from Walmart, but since I got these free I figured it would work for a first solar project that I will likely screw up anyway.
I figure my first step is to determine if the batteries are good and can take a load as designed.I numbered the batteries, took initial voltage readings, then charged all the batteries with a 3amp microprocessor controled auto charger.
I am thinking the best way to 'prove' each battery is to put a load on each battery and record voltage reading over a period of time, down to a target voltage.
I soldered wired connectors to to a 120v 150w halogen bulb (tube type for a work light). It barely lights up and the voltage on a battery drops slowly (.01 very 3 seconds or so). I tried soldering a couple 120v75w bulbs for a load but couldnt get solder to stick to light bulb base.
My question is what voltage should I test them down to. I read somewhere that 12.2v is a good target DOD, and a good guide for the lowest dod for healthy batteries. Should I record voltages every 5 minutes down to 12.2v and graph each battery? A sudden fall off in voltage would be an indication the battery is exhausted or has a bad cell, where a gradual decrease over a long period of time should signify a healthy battery?
Comment