Lithium Battery Advice

sgh77 · 10-08-2015, 02:06 PM

Hi, Im going to park up my Windjammer 3008w empty for six months in the height of summer, while Im overseas.
It has 600Ahr of Lithium Batteries and 1200w of solar on the roof.
What is the best way to protect the batteries? Is it ok for them to remain fully charged? Or do I set a daily timer to use some battery power?

**Herk7769** · 10-09-2015, 07:40 AM

What model battery are you using?

sgh77 · 10-09-2015, 12:22 PM

Quote:

Originally Posted by Herk7769

What model battery are you using?

Lithium Ion Phosphate,
Sinoploy 4 Cell 13.2v,
3x200 A/hr.

**Herk7769** · 10-09-2015, 03:20 PM

Those are pretty cool batteries!

While I have no experience with them but I found this.

BU-702: How to Store Batteries â€“ Battery University

They say that they need to be stored at 40% capacity for long life and not 100% like lead acid.

"While lead acid must always be kept at full-charge during storage, nickel- and lithium-based chemistries should be stored at around a 40 percent state-of-charge (SoC). This minimizes age-related capacity loss while keeping the battery operational and allowing for some self-discharge."

and this

"Finding the exact 40 percent SoC level to store Li-ion is less important that removing some charge and voltage serves as a handy fuel gauge indicator. At 40 percent charge, most Li-ion has an OCV of 3.82V/cell at room temperature.

To get the correct reading after a charge or discharge, rest the battery for 90 minutes before measurement. If this is not practical, overshoot the voltage on discharge or charge by 50mV. Discharge to 3.77V/cell or charge to 3.87V/cell, and the rubber band effect will settle the voltage at roughly 3.82V. Figure 1 shows the typical discharge voltage of a Li-ion battery."

How you do that is beyond me...

sgh77 · 10-09-2015, 07:26 PM

Quote:

Originally Posted by sgh77

Lithium Ion Phosphate,
Sinoploy 4 Cell 13.2v,
3x200 A/hr.

Im wondering if I can just set a timer and run something a few hours a day. They are said to easily handle 3000 cycles of 50% discharge without loss of capacity. So maybe rather than a 40% state of storage keep them in a state of constant daily usage?

Jim Schings · 10-09-2015, 07:40 PM

Very cool batteries. We started using them in some formula race cars with a 75% reduction in weight. Also the immediate cranking power is awesome. There are Lithium Ion Phosphate battery chargers that you can get from wherever you got the batteries. Typically they have a normal charge mode and also a "storage mode". They are smart enough to keep the batteries at the proper storage level. Whoever sold you the batteries should have advised you of this...

Here is the one we use. http://shoraipower.com/chargers-c43

**Herk7769** · 10-09-2015, 08:31 PM

It never fails to amaze me at the quality and breadth of knowledge of our members. Kudos to all who aid those in need.

Kenny kustom · 12-09-2015, 11:21 AM

Do you have any pics and info on your battery pack?

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**Flybob** · 12-09-2015, 11:54 AM

If you are storing the unit for six months. I would discharge the battery to 40% and disconnect it. I will remove it and store it in a cool dry place. The worst thing you can do to lithium batteries is to leave them sit at full charge. Doing that will dramatically reduce the life expectancy of the batteries. Also although LiFe batteries are much safer than LiPo I would still not charge unattended for an extended period of time.

sgh77 · 12-09-2015, 12:37 PM

Quote:

Originally Posted by Kenny kustom

Do you have any pics and info on your battery pack?

2016 Sabre 36QBOK
2015 Ram 3500 CUMMINS

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Dont have a photo of my setup, but here is a photo of a 400Ahr battery on the bench, before they worked out they couldnt fit the larger ones. That is an A4 (letter) piece of paper. Mine are 3x200Ahr.

Witch Doctor · 12-09-2015, 12:50 PM

Quote:

Originally Posted by Flybob

If you are storing the unit for six months. I would discharge the battery to 40% and disconnect it. I will remove it and store it in a cool dry place. The worst thing you can do to lithium batteries is to leave them sit at full charge. Doing that will dramatically reduce the life expectancy of the batteries. Also although LiFe batteries are much safer than LiPo I would still not charge unattended for an extended period of time.

Now you got me wondering Flybob. I know it's not exactly the same but it's still a big battery pack, it is for my wife's scooter. It will get 26 miles on a single charge at 30 mph's. I was told and also read to charge the battery after every use, the charger supplied will shut off after reaching full charge. They said it will be good for 1500 cycles. Also has no memory effect. Is this true about lithium batteries? I know nothing about them but a replacement cost 460.00. They do supply I special charger. Don't mean to high jack but the thread is about lithium batteries. T/U in advance..

Kenny kustom · 12-09-2015, 01:01 PM

Quote:

Originally Posted by sgh77

Dont have a photo of my setup, but here is a photo of a 400Ahr battery on the bench, before they worked out they couldnt fit the larger ones. That is an A4 (letter) piece of paper. Mine are 3x200Ahr.

That's beautiful.

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Kenny kustom · 12-09-2015, 02:48 PM

Quote:

Originally Posted by sgh77

Dont have a photo of my setup, but here is a photo of a 400Ahr battery on the bench, before they worked out they couldnt fit the larger ones. That is an A4 (letter) piece of paper. Mine are 3x200Ahr.

Do you mean 4x200ah?

3 wouldn't make 12v

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sgh77 · 12-09-2015, 03:19 PM

Quote:

Originally Posted by Kenny kustom

Do you mean 4x200ah?

3 wouldn't make 12v

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Yes 12v, yes 3x200ah.

Kenny kustom · 12-09-2015, 03:31 PM

What do you mean by 3x200ah?

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Kenny kustom · 12-09-2015, 03:44 PM

Are you saying, you took 12 cells and made 3, 200ah 12volt batteries?

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sgh77 · 12-09-2015, 03:55 PM

Quote:

Originally Posted by Kenny kustom

What do you mean by 3x200ah?

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My system is three batteries, they are each 200 amp hours each, I have six, 200w 36v Solar Panels, controlled by three 40amp MPPTs, it is a 12v system.

Kenny kustom · 12-09-2015, 04:05 PM

What are you using for a charger..
Besides the solar..?

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Kenny kustom · 12-09-2015, 04:13 PM

Sorry for all the questions..
There's just not a lot of real world info out there.

Thoughts on the battery setup?

I just looked at your location.
You probably see a lot of your type of setup.

I'd like to see your Holden too!!!

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sgh77 · 12-09-2015, 05:16 PM

Quote:

Originally Posted by Kenny kustom

What are you using for a charger..
Besides the solar..?

2016 Sabre 36QBOK
2015 Ram 3500 CUMMINS

I am nice!

Im using an Inverter Charger a TBB 2590F (?). However never need to charge off shore power or generator. We run a lot of 240v appliances, Coffee Machine 1650w, Kettle 2200w, Vaccum Cleaner 2000w, Toaster, Microwave, 40in and 32in SmartTvs, Sstelite Box, WAN Modem, etc... we have just come out of winter into Summer, on a sunny day when Im running the toaster I am still charging the batteries. (More power coming in from Solar than toaster is drawing).

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