We haven't thought of a place to put the battery. Since we are aiming for a simple tool, i believe that there is no need for the elderly to change batteries all the time.
The tool should have a rechargeable battery that can last multiple tasks. Also there should be a clear and bright color on the place where the charge should be plugged in. A bright color around the hole that the plug will be place will be useful.
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I have placed the battery to be on the uppen handle. The battery should be as light as possible, therefore as far as I know the lightest batteries are the ones made out of Li-Ion. Light-weight is an another advantage to maintain. I hope you agree on the design I have uploaded. Let me know about your opinion regarding this feature.