justoneman wrote:The only place I see a secondary battery fitting is in the cabin rear hatch area. This poses a bit of a problem. I have some concerns about gasification especially during charging. If I am charging a battery in the hatch area I would have a power cord coming out of the vehicle so I suppose the simple thing and the minimal thing to do is simply crack the hatch open a bit during charging.
With due respect to Don, I am daily driving a lead sled with 720 lbs of flooded lead acid batteries in the passenger compartment, and have done the same with flooded nicads. The off-gassing is very easy to deal with, as hydrogen is the lightest gas we'll ever encounter, and nontoxic to breathe (though you'd asphyxiate at very high concentrations). The explosion-proof muffin fan that ventilated my battery box failed many recharges ago (and got scarily hot in the act of failing), but the simple act of opening and closing a door brings hydrogen concentrations waay down, even if you forgot to crack a window during recharge. My converted RX-7 EVen has an open -frame contactor inches from the front six batteries, but passive underhood ventilation has sufficed to prevent explosions for the past 25 years of electric operation. The lower explosive limit for hydrogen is 41,000 parts per million, compared to 50,000 for Natural Gas, which lingers much longer than hydrogen... Here's a nice article on how they evaluated the hydrogen hazard on electric submarines. https://www.nap.edu/read/12032/chapter/9#153
That being said, I do have one acquaintance who experienced a hydrogen incident. His converted compact pickup truck had an open frame contactor above the battery pack, both of which were under the bed. On a windless morning after a full recharge, the contactor's spark lit off the hydrogen and actually caused the bed of his pickup to bulge noticeably upward, though no other damage...
I conducted experiments with hydrogen during college, and became pretty proficient at making incendiary balloons via electrolysis without blowing the dormitory's breakers (or my room). It's a great party trick, maybe worth a reprise at an EV car show!