I have serious doubts about battery yard tools - the current generation are mediocre compared to traditional plug in or gas and you can bet those batteries are not going to be cheap to replace when they die.
They may have the power of gas (in one specific tool under certain testing conditions which will never be encountered in the real world) but what about battery life?
A homeowner is going to use a trimmer at most once a week, a chainsaw occasionally and a leaf blower once or twice a season. That's a lot of down time for the batteries.
A pro is going to use a trimmer for several hours every day, 7 days a week. Same with blowers when it's leaf season. How long are the batteries going to work on a charge and how fast do they recharge? How many landscapers are going to bite on a bank of batteries and multiple mobile chargers in their fleet of trucks to power these things on the road... and how long do you think the battery will last being recharged several times every day? Life cycle would probably be less than a full year in that case. The blower style they are introducing is not widely used by pros either - backpacks are the style of choice because of the power and ease of use. Those hand held ones are much weaker.
That's still the biggest drawback to electric cars - limited range from limited battery size and recharge speed/capability.
I personally can't see any real need for battery yard tools outside of a hedge trimmer (that shares batteries with another tool you already use regularly) or a lawnmower. Simple precautions alleviate 95% of the mechanical issues in power equipment, and it'll start and run fine almost every time. Just started my generator last night after a power failure after 5 pulls. Longer than I would have liked, but it was sitting ready to go untouched for 2 years with treated low ethanol gas.