A question that has been posed to me a few times now has been why the Orion Explorer 1 Robot kit comes with an AA battery box and not some bespoke battery decision. I’d like to explain why this was chosen.
The first is that these are easily replaceable. Specialist batteries would be hard to replace and expensive. Rechargeable batteries do eventually stop charging, and those made for a single product tend to end up impossible to replace - have you ever tried to get replacement batteries for an old laptop? AA’s are ubiquitous - that is, they are really easy to find.
Another thing is the cost - cost is important to me with this. Specialist batteries are expensive to develop, and expensive per part. Specialist charging hardware on the robot would also increase its cost, complexity and weight. AA batteries come in a range of prices - and can be bought in bulk for education or for serious gadget geeks.
Weight - while Lithium Ion/Li Poly batteries, weight for weight would probably be more weight effective than AA’s, but may not be able to provide the current needed for driving motors comfortably. Lead Acid batteries would deliver the current, but are quite weighty.
Shipping - shipping largish batteries is actually a little complicated - they can be risky. An AA battery box means the customer can easily source their own. Many couriers refuse to take batteries without a premium or special service because they have a reputation for causing damage, from leaking to actually becoming a fire or explosive risk. This complicates shipping from manufacturers to Orionrobots, and from Orionrobots to customers.
Battery Technology - AA batteries have not been the leading edge of the technology, far from state of the art, but they have been changing. They are becoming higher capacity, able to deliver higher currents and are seeing battery chemistry improvements. If there was a bespoke solution - it would be harder to later modify to accept newer batteries.
In short the main reasons are a little bit of future proofing, keeping costs reasonable and the size/weight of the robot. There is no reason a customer couldn’t modify it and add in a different battery type of their choosing - an RC pack or similar if they wished to. Personally - I’ll stick to my AA’s.