I have a college project due within a week, and it involves a 00 Watt solar panel and a 2V 7.5Ah Battery. I got the project finished up and producing free energy for my house in September, however recently the battery I bought, that was specifically made to hold Solar Power, lost its charge (unsure how or why) and it is pretty much useless. Can I just go to a store and buy any 2V car battery to use?
well the thing to remember just like any rechargeable battery they don;t respond well to continues charging they need some down time to discharge and then recharge. during the charging process the liquid or battery solution get hot and even evaporates. Replacing the battery solution with water won't work when your battery has lost it's solution you need to get battery acid replacement or battery repair solution. this is sold in many location near where the batteries are sold. check your spec for your solar panel out put and take those specification to your local auto store and they might even suggest an over sized battery. you might consider adding an additional battery in series for additional power storage.you might also using a light sensor and cut off switch solenoid which which stop charging or which would also stop and current from returning back to the panel. if you have every own a small car the battery is much smaller than that of a pick up. be sure that you don't get the small battery look for a large heavy duty battery all sold in the same store.
A 2 volt battery is a 2 volt battery. Some are larger than others. Sure you can charge a car battery with a solar panel, but 00 watts for a long time could be a problem. There's one way to find out.
Those answers are partly correct. You cannot recharge two 2 volt batteries in series with a photovoltaic panel with an open circuit voltage of 8 volts. You possibly over charged your 7.5 AH battery with a 00 watt photovoltaic panel, which can supply 8 amps to the battery with unusually bright sun light = fully charged in one hour. More likely you did not charge the battery for a month or more which killed it. Also discharging below 2.6 volts shortens the life of the battery, or short circuiting the terminals even briefly. Yes a deep cycle sealed lead acid battery rated 2 AH is likely the best unless you buy a 00 amp hour marine battery which weighs about 80 pounds and will take at least two days of bright Sun to fully charge.
