Realistic cost for a 30AH 24v Lithium pack ( or similar )

[cj7hawk]

Hi All,

Not looking for an actual battery to buy - more just a realistic guide as to what it should cost to get something around 60AH minimum @ 24v or in another way, anything around 1.5kWh at another voltage...

As in a feasible all-up cost - DIY estimates would be OK ( zero for labor costs ) but all components, mounts, housings, brackets etc, should be included.

I'm thinking it would be around US$800 or thereabouts based on costs on Ebay - Would I be far off the mark? I've made poor estimates before based on overinflated battery specifications, so would prefer an idea from forum members as to what they would expect to pay for something like this.

And I'm assuming that the battery would deliver the full rated output too - eg, would be able to deliver around 1.5kWh - working off of fairly low loads ( around 300W continuous use ) and I'm assuming something that would still deliver well more than half the full rated output after 500 charge/discharge cycles.

Feel free to correct any obvious misconceptions I have about batteries in the response from what I've said above - and any responses are greatly appreciated -

Thanks
David.

 

[Punx0r]

Used: Nissan leaf modules: 7.4V @ 60Ah, already come in a metal can with screw terminals, just series connect 3 modules together. Usually $100 per module, from memory.

New: A123 AMP20 LiFePO4 pouch cells, 3.3V @ 20Ah, 7-series, 3 parallel, need casing. $70 per cell ($1470 total).

Or 18650 can cells: easier to package, smaller/lighter than LiFePO4, probably similarish price.

For Chinese pouch cell packs see PingBattery

BMS: add ~$50 for you probably cell count and discharge rate

 

[cj7hawk]

Used: Nissan leaf modules: 7.4V @ 60Ah, already come in a metal can with screw terminals, just series connect 3 modules together. Usually $100 per module, from memory.

New: A123 AMP20 LiFePO4 pouch cells, 3.3V @ 20Ah, 7-series, 3 parallel, need casing. $70 per cell ($1470 total).

Or 18650 can cells: easier to package, smaller/lighter than LiFePO4, probably similarish price.

For Chinese pouch cell packs see PingBattery

BMS: add ~$50 for you probably cell count and discharge rate

Thanks for that - looks like need to add about 60%~100% to my estimates -

That's very much appreciated -

Thanks for the pointers to pingbattery - I assume their capacity estimates are more or less accurate?

 

[Punx0r]

Thinking a bit more about the 18650 route, if you want to draw only 300W from a 1500Wh pack (0.2C) that would allow you to use high energy density cells. The current highest are 3500mAh, but the Panasonic NCR18650PF at 2900mAh offers better value for money. They're 2.90 euros each in quantity from here:

http://www.nkon.nl/rechargeable/18650-size/panasonic-ncr18650pf-3-7v-2900mah.html

(You may find a U.S. distributor cheaper).

That converts to $3.22 a cell.

2.9Ah x 3.7V = 10.73Wh per cell. 1500Wh / 10.73 = 140 cells, approx. at a total of $450. You'd need to spot weld or compression-fit them into a pack (time/cost).