EZGO TXT Lithium Upgrade

[agpfl]

I am leaning towards the http://www.hybridautocenter.com/HAC4...rts&Itemid=605 kit. Just been unsuccessful contacting anybody at HAC to discuss what additional will be needed for the install. Also want to discuss future upgrade options, ie adding additional cells.

[BobBoyce]

Originally Posted by cgtech

I have info on 2 different 100ah cells of the type you are looking for, if you want.

Here's a link to some LiFePO4 200ah cells I was looking at for a EV build that has since been retired. http://elitepowersolutions.com/produ...roducts_id=149

I looked through what they offer and I like what I see. Thank you.

Originally Posted by Volt_Ampere

You still need to strap them all together physically and electrically. It is very easy with the Leaf cells - not as easy with other cells.

I think these two are well integrated, both mechanically and electrically.

http://elitepowersolutions.com/produ...roducts_id=236

or

http://elitepowersolutions.com/produ...roducts_id=257

[BobBoyce]

Originally Posted by impaper

I am leaning towards the http://www.hybridautocenter.com/HAC4...rts&Itemid=605 kit. Just been unsuccessful contacting anybody at HAC to discuss what additional will be needed for the install. Also want to discuss future upgrade options, ie adding additional cells.

My primary issue with the Leaf battery systems is whether or not the cells are from used Leaf packs. If so, the usable life left in them is an unknown. Hard to beat the price though.

As for what you will need, You will need a pack, battery management system, and a charger. You want the system to have overcharge protection, undervolt protection (to prevent cell damage) and everything else required to use the system in a cart. Here is a link to a complete 36V 60AH system with brand new cells, from that company that cgtech linked to

http://elitepowersolutions.com/produ...roducts_id=194

The price is higher but you get everything required to put it to use.

Bob

[cgtech]

I consider the 60ah to be a little undersized for anything other than basic use, here's why.... Overkill makes for happy battery life, and the 60s are only good for 180a continuous draw, and "depth of discharge" per use could easily go unfavorable. The smallest packs I have done were 80ah (40ah 16s2p), I consider them equivalent to a stock Rxv T-1260 pack and wouldn't go smaller.

[adriftatsea]

Originally Posted by cgtech

I consider the 60ah to be a little undersized for anything other than basic use

Agreed. I use 120ah (2 Nissan leaf cells) in my cart builds.


You are basically fighting 'voltage sag' when under load by spreading it between parallel battery packs.

Aside from money (about $3500), you'll need a way to crimp new 0/2 wire, adding some angle iron and all the tooling that requires, a way to reprogram your controllers lvc/hvc/misc-battery-info, a shunt based volt/watt meter, and I'd recommend flashing a Delta-Q charger to a lithium profile and mounting it onboard.

No real great BMS options exist for packs this large. You either spend $1000 to protect a $2000 pack, hack a chinese bms with worthlessly small bleed resistors to trip a relay across the keyswitch or something, or (my preferred method) is to use good judgement and obsess over pack health data :). Your controller should have a throttle ramp feature at X% battery, the cycle analyst can do closed loop throttle control to target watt usage (vs speed like most controllers do) at low voltage ranges, and the controller also will have a way to trigger high and low voltage conditions. In short, theres lots of ways to notice problems without a BMS.

[scottyb]

Originally Posted by adriftatsea

Agreed. I use 120ah (2 Nissan leaf cells) in my cart builds.


You are basically fighting 'voltage sag' when under load by spreading it between parallel battery packs.

Aside from money (about $3500), you'll need a way to crimp new 0/2 wire, adding some angle iron and all the tooling that requires, a way to reprogram your controllers lvc/hvc/misc-battery-info, a shunt based volt/watt meter, and I'd recommend flashing a Delta-Q charger to a lithium profile and mounting it onboard.

No real great BMS options exist for packs this large. You either spend $1000 to protect a $2000 pack, hack a chinese bms with worthlessly small bleed resistors to trip a relay across the keyswitch or something, or (my preferred method) is to use good judgement and obsess over pack health data :). Your controller should have a throttle ramp feature at X% battery, the cycle analyst can do closed loop throttle control to target watt usage (vs speed like most controllers do) at low voltage ranges, and the controller also will have a way to trigger high and low voltage conditions. In short, theres lots of ways to notice problems without a BMS.

And that my friends is why this is not a battery pack upgrade for the masses.
Thank you for the information.

[agpfl]

My cart is only for basic use 5-10miles. If 15 miles was the max and I had the correct discharge meter in place, that would work for me. One of the questions I want to ask HAC is in the future, if I decide to get the XCT500PDS from Scottyb, will this pack support just adding in the 2 additional battery modules.

[Volt_Ampere]

I went with the 120AH Leaf battery - 14 modules. It only weighs 110 pounds and I have plenty of capacity. I could have got by with the 60AH setup but I like having plenty of margin. Yes they are used but the car mine came out had 300 miles on it. :-(

[agpfl]

Just spoke with Nick. I am going to go with the http://www.hybridautocenter.com/HAC4...led&Itemid=605 assembled pack and 10amp charger. The BMS that comes with the pack can be reprogrammed later if I decide to add in 2 more modules for 48v. The charger is also capable of be modified for 48v operation as well. This should work out well for me because I get my Lithium batteries now for around the same price as 2 sets of Lead. I can always upgrade my controller and add in two more modules in the future providing longer run time and more power.

[DaveTM]

Originally Posted by scottyb

And that my friends is why this is not a battery pack upgrade for the masses.
Thank you for the information.

I agree.....I'm gonna do my install.....right after I have one more drink....