I'm sure you've both seen and by now gotten tired of this discussion, but storing your high capacity/discharge lithium batteries literally in your home (or apartment, doubly so!!) is unsafe. In NYC alone this year there where 13 deaths directly attributed to li-ion bike batteries exploding from thermal overrun..
Unlike say, justifying using candles or incense because you may have a fire extinguisher......a battery fire will not yield to common extinguisher chemicals. All year round FDs are stuck taking a whole day to monitor/extinguish a battery fire, usually after it's gutted a multi famaly apartment.
Or, maybe HN can tell me I'm wrong finally and that the e-bike battery fire pandemic is over? I am afterall a lazy stay at home who hasn't been on a bike in ages :p