Newbie with some questions

[rlw]

Interesting discussion - too bad the thread title isn't something like "Hybrid conversion"...

I know they're currently (pun not intended!) pricey, but have you considered lithium batteries? There's an even greater weight reduction over lead-acid batteries (about 1/5 the weight), and these (http://www.lithiumion-batteries.com/...attery-kit.php) are 40AH.

I'm a noob regarding lithium (what the heck, I'm a noob when it comes to lead-acid, too!), but from what I've read, 40AH lithium is equivalent to 2-3 times the capacity of lead-acid, since they have a lower depth of discharge.

RLW

[KLA]

Originally Posted by rlw

Interesting discussion - too bad the thread title isn't something like "Hybrid conversion"...

I know they're currently (pun not intended!) pricey, but have you considered lithium batteries? There's an even greater weight reduction over lead-acid batteries (about 1/5 the weight), and these (http://www.lithiumion-batteries.com/...attery-kit.php) are 40AH.

I'm a noob regarding lithium (what the heck, I'm a noob when it comes to lead-acid, too!), but from what I've read, 40AH lithium is equivalent to 2-3 times the capacity of lead-acid, since they have a lower depth of discharge.

RLW

Yeah, I looked at them. Too pricey for now. Also LiIon or LiPO4 batteries are very finnicky regarding charge/discharge rates and so on, requiring a battery management system.

I think the most fun conversion, albeit very hard to source in the US, would be the drivetrain of a european diesel Smart car. 800cc, 40 hp 3-cyl common rail turbo diesel, dual clutch automatic transmission. Engine and drivetrain designed to be one unit with the rear axle assembly. Whole drivetrain unit weighs less than a 48V golf cart battery pack alone.

After all, the Smart car is basically a streat legal golf cart

[Hypersprint]

As soon as I win the lottery I'm going to get a set of the 200AH Lipos

[KLA]

Speaking of batteries,

although Li based batteries get the most press, there are other, cheaper battery technologies than Li that would be more suitable for a golf cart.

For example the NiZn batteries described here:
http://www.powergenix.com/?q=nizn-batteries-in-hevs

NiZn batteries have better peak current capability, survive more charge/discharge cycles and have half the weight per Wh compared to lead acid.
And because of the materials used, should be the same or lower in cost.

I wonder why golf cart manufacturers or battery suppliers have not looked closely at that.

[JohnnieB]

Originally Posted by KLA

.....................I wonder why golf cart manufacturers or battery suppliers have not looked closely at that.

The obvious answer is unproven technology coupled with low supply and little demand, then toss in a bad economy.

Deep cycle Lead-Acid batteries are based on proven technologies that have been around for over a century, the demand is thoroughly entrenched in the consumer base and there is fair market competition in the supply chain.

Unless the pseudo-geniuses at EPA come up with a new pseudo-science to outlaw Lead-Acid batteries, which are 100% recyclable, I suspect they will be the primary means of powering electric golf carts for the foreseeable future.

[Hypersprint]

Originally Posted by JohnnieB

Unless the pseudo-geniuses at EPA come up with a new pseudo-science to outlaw Lead-Acid batteries, which are 100% recyclable, I suspect they will be the primary means of powering electric golf carts for the foreseeable future.

SSSHHHHHHHHHH don't give them any ideas

[KLA]

Originally Posted by JohnnieB

...Unless the pseudo-geniuses at EPA come up with a new pseudo-science to outlaw Lead-Acid batteries, which are 100% recyclable, I suspect they will be the primary means of powering electric golf carts for the foreseeable future.

I have no doubt they will. I live in the PRC, the Peoples Republic of California, and our CARB is worse.

However, with regard to the NiZn Technology, they are looking at the car market and apparently are already testing a battery to replace the normal lead-acid starter battery. With its peak current capability, large number of fast charge, discharge cycles and deep cycle capability its a shoe-in for the Micro-Hybrid (engine start-stop automatic) market. Once that is established, the golf-cart market could be one of the beneficiaries because you won't need a special deep-cycle version.

[KLA]

A friend sent me this:

http://www.wired.com/images_blogs/ga..._datasheet.pdf

Unfortunately I will have to wait before that is in production, if ever .
But not too shabby,

A 5 kW generator that weighs 22 lbs, incl. fuel, and is, based on what I remember of the Sachs KM3 engine design, just slightly larger than a single golf cart 6V battery.

[Hypersprint]

It will be fun sitting around a camp fire having a few beers one day while we are talking about the good old days when we had lead acid batteries in our carts

[KLA]

Originally Posted by Hypersprint

It will be fun sitting around a camp fire having a few beers one day while we are talking about the good old days when we had lead acid batteries in our carts

We won't, unless the camp fire is equipped with catalytic converter, smoke particle filter/scrubber and uses EPA certified low carbon wood, and you have a camp fire operators license (@ $500/annum)