The idea the homeowners insurance doesn't cover the homeowner being negligent or stupid seems to betray a misunderstanding of what homeowners insurance is generally used for, namely protecting the mortgage lender from a catastrophic loss of the property's value.
In this case, since I don't have a mortgage, it is really covering my losses. Should my house burn down I don't want to have to go out and pay to rebuild it. I'm willing to take the actions the insurance company requires in order to keep their actuaries happy.
For anyone who isn't aware, California has seen a number of large scale disasters over the last couple of years which have destroyed many homes. From the fires in Santa Rosa to mudslides in Santa Barbara. And I have a number of friends and acquaintances who have been having painful discussions with their insurance companies about what they will and won't cover. I am fortunate that I have not suffered a loss. Seeing that pain though led me to call up and have a long, recorded, and detailed discussion with my insurance company about how they decide what to cover and on what basis they feel entitled to deny a claim. As with people who have actually lost their homes I was surprised at the number of things that they would use as a reason for not paying a claim.
One consistent theme was "unusual hazards that the insurance company was not made aware of." This ranges from people who have turned their garage into a place to do car repairs (adding lifts etc) to people who brew beer under the sink in the kitchen.
On the basis of that conversation, and the assumption that my insurance company was 'typical', I don't expect the battery fire to be covered. :-)
In this particular case I recorded it :-) (with the permission of all involved) so that in the event there was some discrepancy about who said what I could refer to the recording.
Not really, there was an interesting digression into the question of using/installing "industrial equipment" (I've always wanted a CNC machine center for my garage.) We have an "industrial" washer and dryer pair (but that was ok). No sense turning this battery example into an insurance thread.
There's a difference between being negligent (leaving the stove on) and performing unlicensed DIY electrical modifications that were not approved by code inspectors and involve storing huge amounts of energy.
Exactly. Insurance will generally cover anything that it doesn't specifically exclude in the insurance documents. If you are walking with a can of paint and drop it and destroy your carpet most homeowners policies will pay to replace the carpet. If you leave the water on in the tub (by accident) and flood your house the policy will most likely pay for it. However it won't cover floods from the outside. But it will cover water that comes in from the roof or through the windows (subject to any exclusion for hurricane potentially).
Likewise if you decide to put together an array of lithium batteries in your bedroom most homeowners policies should cover that. After all those batteries already are in products in the house (as opposed to gasoline which would only exist in a lawn mower in small quantities in the garage).