Carl, what you've described regarding lead/acid batteries is one of the two ways to get a "dead cell". The other is when continued shock (both physical and thermal) and vibration cause some of the lead within a cell to break off from the framework that holds it, creating a short circuit between the plates in that cell. If the break is below the level of the acid, it just causes that cell to completely discharge, and s relatively safe, though it ruins the battery. If, however, this happens above the battery's acid level, the results can be pretty spectacular. the high current spark generated when it shorts out ignites the Hydrogen Sulfide gas within the battery and causes a fairly large explosion within the cell which can literally rip the battery apart. It's a really rare occurrence, but I've seen it happen twice in my career as a mechanic. Sadly, one of those times, my face was in close proximity to the top of the battery, and with no eye protection (I was working the carb on an old Buick, trying to get some fuel into it while a friend was pushing the starter pedal {yes, the starter "switch" was on the floor}). The explosion sent me to the hospital, and very nearly took my sight permanently. As it was, my eyes were bandaged for over a week, and I was effectively blind for another 3 days after that. NOT pretty. I learned my lesson, though. No more working on cars without proper eye protection.

Dave,
I didn't realize you were a mechanic, some of my best friends were mechanics.  Anyways I'm not sure what you were referring to, basically I was saying if the car doesn't start don't kill the battery.  Then I went on to say if ( and this is talking about a series of NiCad cells ) measuring the voltages find the weak cell and charge it individually.
  In a car battery everything is sealed in one package and there is not much that can be done, now you can bring it to an auto store where they can test the battery and alternator. 
  I'm still learning about the electric cars, seems they can use about any motor, ac or dc, brushes or dc without brushes.  Since they have a whole floor filled with batteries I'm wondering how these are wired.  I actually don't even know the voltage of 1 cell of a lithium battery.
  Sorry to hear about your misfortune Dave.
Carl2

That misfortune was over 30 years ago, so no worries. All I have to remember it by are a couple of small scars on my face, and a deeper respect for safety practices, so it's all good. I was a mechanic for over 25 years, before my hands and shoulders gave out, preventing me from being productive enough to keep at it. After that, I've just tried different fields (cab driver, casino change person, etc.), but nothing really fueled my psyche as much as web development and graphic design, so that's what I'm working toward. I think it would be interesting, and certainly more cost effective to the consumer if car batteries were modularized, allowing for individual cell replacement, but then Walmart couldn't charge $100 for a small, under-powered battery for a Yugo. Perhaps with enough tech breakthroughs in EV battery technology, the lead/acid batteries in gas/diesel cars could go the way of the dinosaur.

It's been a journey of discovery for me this thread. I still want an electric car, for me the pros do thrash the cons.

Went into Brighton town center today kept my eyes open for an electric car, didn't see any, them 8 public chargers will be all mine 

  Interesting but I find myself filled with questions,  a look for info on lithium batteries shows 12 volt batteries, an impressive 99 WH battery for 529, weight 3.5 lb.  Since it is an automotive part it probably has a lifetime warranty which means when it fails the lifetime has ended, joke.
  Since we are dealing with nice clean electricity I tried to found out how the electricity I buy is generated but was unable to.
Carl2

The batteries in the electric cars come with a warranty, if we look at the Nissan Leaf for example it has a 5 year or 60,000 mile warranty on the battery.

QuoteNissan LEAF battery packs are warrantied against a capacity loss of 9 bars (approximately 70 per cent of the battery pack's original capacity) for a period of 60 months or 60,000 miles.

Renewable or green energy production needs to increase and it will over time, I believe 

For me this is also about getting pollution out of our towns, the places we live in, when I got into town these days I smell the fumes, if there were more electric cars on the road that would reduce pretty quickly.

This is going a little off topic but what the heck. 

Interesting energy density comparison.

A lead acid cell is 2.1v to 2.3v depending on the electrolyte. Lithium Ion appears to be 3.3v to 3.7v.

Some good info there Snowy 

Correct me if I'm wrong but it seems lithium ion gives the best energy density to date for rechargeable batteries.

  Excellent info at that site, and the lithium battery shows light weight, small size, low internal resistance and can be recharged in 1 hours time. Going from 8 hours at 16 A, 4 hours at 32 A, 1 hour at 128 A should be what needs to be put in. 
  Even charging at 32 A means major rewiring plus special purpose wire and connectors.  I wonder how many amps can be taken from the public access recharge stations.
Carl2

Lower voltage could be a little problem for some countries that have it, the USA springs to mind, pretty sure we have almost double the voltage in Europe.

Superchargers found on our motorways in the UK can supply up to 225 amps , it must result in a much faster charge.

  In the US we have 120 Volts supplied by the standard wall outlet, for the stove there is a 3 phase outlet that supplies 220 volts.  The voltages are thought to be constants and the current A is dependent on the resistance or load. 
I'm not sure what size wire would be used to carry 225 amps, there is a table you'd go to, The wire for 128 amps was pretty heavy.  Nice to see that England is prepared for the electric car, looks like you're leading the way.
Carl2

Lithium ion in it's various guises is by far the best for energy density.

Europe is all 230V AC (UK nearer 240V) single phase and 400V (UK 415V) three phase. Standard ring/loop of 32A which would give 96A three phase. (3 x 6mm²). Cable current loads diagram.

225A at 60C (140F) would be 150mm² cable. Hmmm! I've played with 24mm². Or 35mm² if you run it at 200C (390F).

I still like the idea of hydrogen fuel cells. You can buy them now but not very good yet. 180W out of a 9kg unit that uses 1.25 litres per kW/h.

Nice reference page, Snowy. I like that there is a conversion chart for AWG to mm². That helps, because I'm quite familiar with AWG sizes.

Hydrogen fuel cells, yes agreed, one day.

I believe this is a 225amp in action.



Carl2, I don't the UK is much further ahead then the US in reality, I know you guys have a much larger area to cover, these things take time.

Norway are the leaders today.
http://gas2.org/2016/01/21/electric-car-sales-surge-in-norway-during-2015/