I have made a 5v dc 52watt solar panel and I going to be trying to charger 4 2v dc 55ah batteries. I get about 6 hours of sun on my panel. Spec below, is that a big enough panel to charge the batteries???I have 30 3x6 solar cells wired together Cell Specifications: (Watts): .75 Wp (Amps): 3.5 Imax (Volts): 0.5 V max which is where I got my 5g 52watt max (if math is wrong plz tell me) The Battery type: 2Volt 55.0ah NB Sealed Lead Acid Battery. I am using a mppt solar charger.
I don't think so, but if it did, it would take a very long time. You need enough wattage or amps to push the power in the battery and 3w may not be enough. You would be better off with a small 2v battery, maybe the type they use for emergency lights. I would use a sealed battery for this type of setup because car batteries are designed for heavy charging with alternators from 60 amps and up.
Technically, any solar panel can charge any battery, but it would take quite a long time do do so if it is a large battery. If you are aware of the voltage and either amp or watt rating of the unit that is usually used to charge the battery, the solar panel should have a similar power output to that charger to work well. amps and watts are quite similar, and can be converted with this simple formula: W=watts; V=volts; A=amps; W/V=A; V*A=W; When charging batteries, it is always wise to use less amps than needed, and roughly the same voltage as the battery being charged. The less amps used to charge batteries means the battery will take longer to charge but will last a lot longer in the long-term. Your solar panel should be sufficient to charge the battery, but you should test charge it to see if it works well. I recommend using a multimeter to check the batteries voltage every couple of hours. Once the battery reaches 2v, it should be fully charged. You should also check the amps in case they are not at the expected value (take caution when checking amps with a multimeter, when i do it i always end up melting my multimeter leads). The battery should be fully charged from anywhere between 6-48 hours. if it is charging faster, the solar panel has too much power. if it doesn't charge in this time frame, the solar panel is not powerful enough.
OK your math on the solar panel looks correct, but you are missing some critical information. What is the load on your batteries and for how long is this load being applied. Calculate the amp-hour load to see if your solar panel can recharge your batteries with the amount of sun light available. A safe engineering standard is to have twice as much capability as required. If you have a 200 amp load for 7.5 minutes, this would be a 25 amp-hour discharge and will take your solar panel over 7 hours to recharge your batteries. Your solar panel can easily charge the batteries up to full capacity with out any load on the batteries, if the batteries are 50% discharged, this will take about 32 hours. CAUTION! I am assuming that you are hooking the batteries up in a parallel connection, that will give you over 200 amps of current. You should charge each battery up to full charge before you connect them together, if they are not at the same exact voltage when you connect them together, they will self adjust so that each battery is at the same voltage level, at 55 amps this could be a very large spark. Each cell, there are six (6) cells in a 2 volt battery, should be at 2.7 to 2.2 volts DC per cell at full charge. Make sure your battery has a voltage 3.02 to 3.26 volts open circuit or no load. This should be full charge if your batteries do not have this voltage level, say one battery is at 0 volts DC, it could have a dead or shorted cell. DO NOT use this battery until you can get it to hold a 3.02 to 3.26 volt DC level.
OK here is my idea that i am in to far to back out For this kind of project, you need professional guidance.
