Thoughts on the Spark Design

We’re launched the Spark, our iPad solar charger, last week (it also charges several other tablets, smartphones and digital cameras). This is our first tablet-specific product and we look forward to everyone’s feedback.

We started thinking about the Spark about the time the iPad came out and looked like it was going to take off. We realized tablet batteries were five times the size of smartphone batteries and charged best off high current ports. We also recognized that our current chargers, while potentially useful for an iPad “boost”, wouldn’t really cut it for daily iPad charging. They didn’t have enough solar power and their batteries only put out 650mA, short of the 2A needed to chare an iPad quickly.

We had a lot of debates about how much solar power and battery capacity we should include. Our belief is that if we underpower a product, the user experience is frustrating and the products aren’t used on a regular basis. If we overpower the product, the cost, weight and size increase.

We settled on 8 Watts which gives about a 1:1 ratio between time in the sun and video playback. Using 17% efficient cells, this makes the solar area bigger than an iPad, but we believe that tradeoff is worth it.

For the battery, we targeted one full iPad charge. We’re a bit over this…most times we’re seeing 1.1 charges, but still this is more satisfying than only getting to 76% full.

The Spark is a standalone case that holds the iPad, your charging cables and a few other items you might need on a trip (I packed my toothbrush and a small paperback in there on a recent trip…yes, I sometimes still read paper books). We don’t currently have plans for something closer to the Amp which would be much smaller and wouldn’t hold the iPad, but let us know if that is something you’re clamoring for and why.