Lithum battery for a 2000.5 DS

[Romrok]

I am setting up to be a dealer for the systems out here in the Bahamas. I believe the system was 1800$. I like the weight savings, but the real reason out here is for the lifespan of these CALB cells. 15 x 3.2v cells and each cell has its own charger with Lithium Boost's own BMS.

We are paying 1900$ a pack of Trojans out here now and most folk are getting and average of 4-5 years out of a pack.
Not charging enough, not checking the water and running packs dead on long trips with heavy loads across some of these out islands in the Abacos lead to even less life on a pack.

We are looking at loosing 300lbs of weight and increasing range and life span to nearly 20 years on a pack. Mind you the system is going to be almost twice the price of lead acid out here, but you will get double the life for that money., and virtually maintenance free.

I believe having a separate charger on every cell will help insure the cells don't get out of balance.

I hope to find some time this weekend to get the system installed and start the testing.

Rom

[Volt_Ampere]

What makes you think you will get 20 years out of a Lithium pack? You need to get 8 to 10 to break even and I would not count on that.

[Romrok]

I would suppose its sales talk, obviously immv. But the battery manufacturer is reporting quite a few more charging cycles than lead acids. CALB is calling for 2000 cycles vs about 3-400 for a good lead acid. I am not sure on the lead acid numbers but I believe that's close.

Edit. Noticed 650 for Trojans

Anyway, it seems like a good idea, I'm gonna run with it and see if I can interest folk in them.

Rom

[sportcoupe]

Originally Posted by Romrok

I would suppose its sales talk, obviously immv. But the battery manufacturer is reporting quite a few more charging cycles than lead acids. CALB is calling for 2000 cycles vs about 3-400 for a good lead acid. I am not sure on the lead acid numbers but I believe that's close.

Edit. Noticed 650 for Trojans

Anyway, it seems like a good idea, I'm gonna run with it and see if I can interest folk in them.

Rom

Trojan says we will get 1500 cycles (4 years) on their T105 if discharged to 60% SOC. If you are more conservative and recharge at 80% SOC then you should get 3000 cycles (8 years). This is the main reason why we recommend buying the highest capacity battery you can afford. If you discharge it less between charges it can last twice as long even though it cost more to buy the larger AH battery.

[Volt_Ampere]

If you take a lithium pack below minimum voltage ONCE it's trashed. The guy I know that experimented with one in a golf cart had it trashed in a couple months when someone drove the cart too long.

[jjance]

If you discharge it less between charges it can last twice as long even though it cost more to buy the larger AH battery.

This statement is sales talk.

[Romrok]

The pack that I have replaced with lithium is a Sam's club set, energizer branding. I have had them in the cart for 3 1/2 years and have not had to put water in yet. I would plug it in after nearly every trip. My trips are usually quick on Man O War. Its a small island. Might have run the pack down low a dozen times.

Now I put in a set of the same batteries for someone else and they burned them up within the year. Not adding water and running them down too far.

According to different places that carry CALB brand batteries they say between 3000-3500 charge cycles at 80%. But that info isn't reliable compared to Trojans site, of course.

The BMS on this pack is connected to the ignition circuit, once pack voltages gets too close to minimum safe levels it will shutdown the cart to avoid damage. There is a limp home button that will allow you to get to safety and charge. It can be used only once per low pack situation.

The cart is a lot of fun to drive, more so with the lithium. Without the excess weight of the wet cells, it pulls up hills better and gets to speed a bit faster obviously.
I an thinking about removing a leaf on each side to soften the ride a bit now.

One of the above posts talk of trojan charge cycles. And I admit they are similar to these lithium cells. So life might not be the best selling point, but the lithiums do have circuits to protect from damage where lead acids can but run down til the cart shutters in many cases causing damage. Someone who doesn't know about electric carts and the quirks for long battery life will destroy a pack quickly. See second home owners below...

The light weight allows for a better range without discharging as far. Maintenance is way lower with acid build up and water to fill.

The area I plan to sell to are mainly second home owners who are environmentally minded and buy electric carts. Also there is no fuel station near this area without going with cans in a boat.
The folk are not all inclined for one reason or another to maintain the carts for connections or water levels, and like to travel long distance over hilly terrain to goto a friends or a place to eat with 4 folk on the cart. This leads to shuttering carts and being towed home a day or two later to charge. They do not understand or possibly refuse to use battery life extending practices.
There are a few trips on that island that I know cannot be done with 4 160lbs persons on board without carrying a charger and plugging in to make the return trip, at least without doing a 20% SoC run. And finding a place to plug in could be a challenge sometimes.
These are the issues I think folk would pay extra for to be rid of. I know its not for everyone.

Rom

[Volt_Ampere]

I would suggest that you do remove some spring leafs because the cart is sprung for the weight of the original batteries plus driver. The guy I know that had some of the first lithium packs said his cart was very top heavy and he was worried about rolling it. His batteries did not protect them selves well enough and they died a quick expensive death.

[Romrok]

Indeed you are correct. The cart won't have that much weight on it again for a while hopefully. I am still designing the permanent hold downs for the pack and charging system. I must say I didn't think of rolling it over to damage a pack, the greatest fear for carts out here is to run them off a dock. The cart the pack is in was a salvaged sunk cart I rebuilt. New Amd 3.75hp to replace the old GE 3.75 and standard 48v harness. Reused the old Curtis controller until just recently when it finally gave up.

Rom

[Furyous]

What does everyone think about this? 48v, 93aH for just under $1400? Seems like a pretty good deal.
http://hybridautocenter.com/HAC4/ind...bms&Itemid=195