How does a car operate safely with a battery?

(2011-03-19 14:25:11) 1. Daydreamare Says: This question stems from my current endeavor to hook up a portable power system for camping. I have a car battery and an inverter, from which I operate appliances in well-ventilated areas. I've learned that batteries emit hydrogen gas, which is okay to inhale (I think), but hydrogen is highly flammable. A small spark can lead to an explosion, plastic shrapnel and sulfuric acid rain.

So I got to thinking about a car engine. Doesn't an engine produce sparks? The car battery rests contiguously with the engine block. I've never heard of a hydrogen explosion under the hood.

So, my question is What makes a car battery safe to use around the engine but not safe to use in an enclosed space, such as the cab of my car?

Thanks to everyone who answers!2. rick29148 Says: The same rules apply, weather you're powering a portable TV or a car. Lead acid batteries do emit explosive hydrogen gas as they discharge/recharge, but in very small quantities. It's just not a problem because of the small quantity & the open environment around the car. Tag: How does a car operate safely with a battery?