Have 3kWh of lithium batteries, need ideas on how to use them

Daox · 08-08-13, 10:55 AM

So, I have a few lithium batteries laying around from a PHEV kit for my Prius. I am not going to attempt to use it in the car as its just been too much hassle for too little gain. But, I have 32 ~30Ah (about 3kWh worth) lithium cells just laying around. So, I'm trying to think of a way to use them... Ideas are quite welcome!

My first idea was hooking them up to a solar panel and running something in the house off of them... Of course this means a little bit of needed hardware. First off I'd need a solar panel, and a charge controller, and also an inverter. Then I thought about it and I really haven't seen solar charge controllers for lithium batteries. I'm sure they're out there but I haven't ever read about them except for tiny electronics like those solar phone charger dealies. Anyone got any links or info or anything?

Daox · 08-08-13, 11:09 AM

A quick google search brings up these guys:

Genasun MPPT Controllers For Lithium Batteries | Genasun

Pricey, but what do you expect when using lithium...

AC_Hacker · 08-08-13, 04:28 PM

Quote:

Originally Posted by Daox

So, I have a few lithium batteries laying around from a PHEV kit for my Prius. I am not going to attempt to use it in the car as its just been too much hassle for too little gain. But, I have 32 ~30Ah (about 3kWh worth) lithium cells just laying around. So, I'm trying to think of a way to use them... Ideas are quite welcome!

Wanna sell a couple? My electric bike could use something like that.

What's the voltage?

-AC

Daox · 08-09-13, 08:36 AM

EV use would be possible, but they really aren't the greatest cells. They're made by Mottcell. I capacity tested every cell with a powerlab 6 charger. At 40A charge/discharge they get fairly warm, so I wouldn't push them past 3C for a short duration. They are LiFePo4 chemistry, so 3.2V nominal. With 32 cells in series that gives you a 102V pack with 30ah or any combination of parallel cell setup. The PHEV kit used them in a 51V / 60Ah configuration. Even in this configuration I wouldn't recommend pulling more than 200A for a short duration, so its really not a ton of power. The new CALB cells blow these things away.

AC_Hacker · 08-09-13, 09:14 AM

Quote:

Originally Posted by Daox

They are LiFePo4 chemistry, so 3.2V nominal. With 32 cells in series that gives you a 102V pack with 30ah or any combination of parallel cell setup. The PHEV kit used them in a 51V / 60Ah configuration. Even in this configuration I wouldn't recommend pulling more than 200A for a short duration, so its really not a ton of power. The new CALB cells blow these things away.

My intended use is an electric bicycle... way different than a car.

My bike currently has an old 10Ah Lithium ion battery (36v). I can barely get to the store & back.

I'm trying to put together a 20 to 30 Ah battery pack. I have seen LiFePO4 packs that are used successfully from Ping Battery.

So, a 10 cell pack would probably work just dandy.

How big and how much do they weigh?

-AC

Daox · 08-09-13, 09:45 AM

I'll have to verify because my cells are a few years old now. But I think the specs are in the link below. I must have the SZ-40, although during capacity testing they didn't come anywhere near 40Ah. The best one I have is about 35Ah, the worst is 29Ah.

æ·±åœ³å±±æœ¨ç”µæ±*ç§‘æŠ€æœ‰é™å…¬å¸

The specs say:
3.3 lbs
4.56" x 1.81" x 7.28"

mejunkhound · 08-11-13, 07:52 PM

Anyone got any links or info or anything

EVERY cell needs a shunt controller. The ones I've used are simply a LM139 comparator feeding the gate of a FET and resistor to limit the INDIVIDUAL cell voltage to <4.1 V (Li-ion) or appropriate voltage for your chemistry.

NeilBlanchard · 08-12-13, 07:27 AM

I'd make a large version of the SOLN1 with them.

Daox · 08-12-13, 08:23 AM

Quote:

Originally Posted by mejunkhound

Anyone got any links or info or anything

EVERY cell needs a shunt controller. The ones I've used are simply a LM139 comparator feeding the gate of a FET and resistor to limit the INDIVIDUAL cell voltage to <4.1 V (Li-ion) or appropriate voltage for your chemistry.

Thanks, yeah I know a bit about charging lithium cells. I actually designed a BMS system for the PHEV kit since the one that came with the kit is absolute junk and ruined cells... The link I posted of that charge controller has none no way of monitoring or shunting power between cells. I wouldn't trust it based on what I've experienced while playing with these batteries.

morphector · 08-18-13, 08:22 PM

I don't know if that would make economic sense but if you've got electricity at an off-peak and on-peak just charge them up off peak and send the power back on-peak....

08-08-13, 10:55 AM	#1
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Have 3kWh of lithium batteries, need ideas on how to use them So, I have a few lithium batteries laying around from a PHEV kit for my Prius. I am not going to attempt to use it in the car as its just been too much hassle for too little gain. But, I have 32 ~30Ah (about 3kWh worth) lithium cells just laying around. So, I'm trying to think of a way to use them... Ideas are quite welcome! My first idea was hooking them up to a solar panel and running something in the house off of them... Of course this means a little bit of needed hardware. First off I'd need a solar panel, and a charge controller, and also an inverter. Then I thought about it and I really haven't seen solar charge controllers for lithium batteries. I'm sure they're out there but I haven't ever read about them except for tiny electronics like those solar phone charger dealies. Anyone got any links or info or anything? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

08-08-13, 11:09 AM	#2
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	A quick google search brings up these guys: Genasun MPPT Controllers For Lithium Batteries \| Genasun Pricey, but what do you expect when using lithium... __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

08-09-13, 08:36 AM	#4
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	EV use would be possible, but they really aren't the greatest cells. They're made by Mottcell. I capacity tested every cell with a powerlab 6 charger. At 40A charge/discharge they get fairly warm, so I wouldn't push them past 3C for a short duration. They are LiFePo4 chemistry, so 3.2V nominal. With 32 cells in series that gives you a 102V pack with 30ah or any combination of parallel cell setup. The PHEV kit used them in a 51V / 60Ah configuration. Even in this configuration I wouldn't recommend pulling more than 200A for a short duration, so its really not a ton of power. The new CALB cells blow these things away. __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

08-09-13, 09:45 AM	#6
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	I'll have to verify because my cells are a few years old now. But I think the specs are in the link below. I must have the SZ-40, although during capacity testing they didn't come anywhere near 40Ah. The best one I have is about 35Ah, the worst is 29Ah. æ·±åœ³å±±æœ¨ç”µæ±ç§‘æŠ€æœ‰é™å…¬å¸ The specs say: 3.3 lbs 4.56" x 1.81" x 7.28" __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.* To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

08-11-13, 07:52 PM	#7
mejunkhound Apprentice EcoRenovator Join Date: Apr 2011 Location: PNW Posts: 197 Thanks: 0 Thanked 47 Times in 31 Posts	Anyone got any links or info or anything EVERY cell needs a shunt controller. The ones I've used are simply a LM139 comparator feeding the gate of a FET and resistor to limit the INDIVIDUAL cell voltage to <4.1 V (Li-ion) or appropriate voltage for your chemistry.

08-12-13, 07:27 AM	#8
NeilBlanchard Journeyman EcoRenovator Join Date: Dec 2009 Location: Maynard, MA Eaarth Posts: 383 Thanks: 78 Thanked 39 Times in 32 Posts	I'd make a large version of the SOLN1 with them.

08-18-13, 08:22 PM	#10
morphector Lurking Renovator Join Date: Dec 2009 Posts: 6 Thanks: 0 Thanked 1 Time in 1 Post	I don't know if that would make economic sense but if you've got electricity at an off-peak and on-peak just charge them up off peak and send the power back on-peak....