The PowerFilm USB + AA solar panel charger can be possibly the best solar AA battery charger product and design you can ever found, it is very useful especially for those backpackers. For stores that have EMS and REI will definitely have to bring along with this type of charger. Generally, we can said this is actually 2 devices in 1. The charger can be a solar charger for NiMH batteries (you will get 2 NiMH Sanyo 2000mAh batteries that attached together when they ship the device). Besides, It's as well can be a voltage transformer which converts the 2.4v of the NiMH batteries and pushs it up to 5v and you are able to use the product to charge your USB device such as your iPod or cell phone with the charged batteries even under the condtion where it is not position under the sun. Which indicate that it is possible to lash the device on your backpack or perhaps car dash and never have to tether your cell phone to it throughout the day, after which draw from the stored energy in the batteries during the night. You can charged 2 batteries at the same time under the sun condtion without any problem and you can just start charging your iPod at the time even the solar panel is fold up and the device will just work flawlessly.
This PowerFilm USB + AA solar panel charger is rated at 5V by having a 1 amp optimum load. In case the device that you want to charge needs more than the maximum load, this isn't going to work. The solar cell charger is rated 3.6 V at 400 mA in full sunlight that is runs in optimized to charge the batteries which attached on the device. To figure out whether the USB device is going to recharge the solar battery, check out the voltage and current on the battery and you will be able to determine Vah (Volt/Amp hour). For instance; if the battery for your cell phone is 3.7 V at 850 mAh = 3.145Vah. This means that the charger is going to take at least 20% extra hours to charge the battery as a result of losses. Therefore in this case, you are going to determine the device will take 4 Vah to start charging the battery. For the AA batteries that are included with the PowerFilm USB + AA solar panel charger are rated 2.5 V (for the pair) at 2000 mAh = 5 Vah. This is pretty much correct for the reason that soon after the battery for your cell phone been fully charged, you will still have sufficient power in the AA batteries to run the GPS for approximately another two hours.
In order to speed all the things, it is recommended for you to put the photo voltaic collectors on anything which is cool with all cells are fully exposed to sun light. By doing so, you are actually charge the USB battery with fully charged AA batteries with the solar collector direct exposed to sun light.
Many users found this PowerFilm USB + AA solar panel charger is extremely good, the device is rather small as well as portable and you will find most of the products are from the USA although this can be vary for different purchase. Once you get the product, you can try to just let it charges, you will find that the light tend to be very solid at all times except in cases where the condition been very cloudy the batteries will lose some of the charges. The device will not charge the USB directly, instead you will need batteries to be as a buffer and this will be better. You will expect the voltage given off by the solar panel can be different and the output power tend to be varied as well. The AA batteries as the buffer let it get some charge as a minimum and provide constant USB power. Therefore considering that the batteries are a buffer, make sure you first charge the batteries follow by begin charging the USB device as soon as the batteries are 100 percent full. You may just let the device keep connected at the time it is charging under the sun, by doing this it can prolong the life of the battery a little bit however because the manual that is included in the box mentioned that users are best to make use of it when it is fully charged. You can just folds it up easily and inserts it in your pocket or laptop case so that you can charge your PDA (Palm TX) since it normally will only get dying after using for the entirely day.
