Testing Lithium batteries - The Gobi Way

gobi

Member
My aim is to test the capacity of any lithium battery I buy before I put it to use.
To get a happy balance between time/current/capacity, I settled on 20 amp draw to test my batteries.

Why 20 amps? Cuz that is my average draw and I had everyday items which I could use to test at that draw.
I can use this to test EVE 280ah, Litto Kala 100ah, A123 batteries or even my scooter packs.

What I used to test:
1. Desktop heater (walmart) - 200 to 300 watts ($10)
2. 400 watts modified sine wave Inverter (I picked this up in the late 90s from a mega truck stop in Iowa around Davenport) ($30)
3. DC Power Analyzer (eBay or any other source) ($10)

For a total of $50, I can test the capacity of my batteries and when I am done, I can repurpose those items.

Here are pics of the components:

Next: I will demo a simple setup of the above.

Keywords: Lifepo4, littokala, 100 ah, 280ah eve cells, lithium battery, capacity tester, A123, topband
 

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Wayne

Administrator
Staff member
400 water modified sine wave Inverter
I have no concept what a "water modified inverter" is.. Please educate me.

(I picked this up in the late 90s from a mega truck stop in Iowa around Davenport)
That would be the Iowa-80 Truck Stop. I've been there hundreds of times and as recently as yesterday, it's on my way home.

Looking forward to your lithium story!
 

gobi

Member
Thread starter
I have no concept what a "water modified inverter" is.. Please educate me.


That would be the Iowa-80 Truck Stop. I've been there hundreds of times and as recently as yesterday, it's on my way home.

Looking forward to your lithium story!
It would If I can type, dang voice > text arrrh, thanks for catching that. Corrected.

Yeah, I-80 truck stop, spend many nights there snoozing, luv the collection of gadgets they have/had. Before amazon and ebay went prime, they had the goods!
 
Yes that is definitely something could be something from the Iowa 80 I have been there it is huge. And let’s just say I didn’t leave empty handed LOL. Also good tips too on testing.
 

gobi

Member
Thread starter
Yes that is definitely something could be something from the Iowa 80 I have been there it is huge. And let’s just say I didn’t leave empty handed LOL. Also good tips too on testing.
Yeah, that place is usually busier at 2 am on a weekday than a walmart at 2pm on a weekend :)
 

gobi

Member
Thread starter
Using the above setup, I will do:

1. EVE LiFePO4 280Ah 3.2v Battery capacity Review
2. Litto kala LiFePO4 100Ah 3.2v Battery capacity Review

I usually stop around 95% capacity, I am good with 95% capacity for the price I paid.

These are new cells (or claimed to be by seller).

280Ah EVE LiFePO4 cells will take around 14 hours to test, I usually do it all in one day or go half way 50% and then complete testing next day as I NEVER leave them unattended during my test.
 

Wayne

Administrator
Staff member
This is completely a new world to me and look forward to your posts. I will have lots of questions :)
 

gobi

Member
Thread starter
Gadgets to test capacity:

This $10 item is the most economical and useful meter to measure the capacity of a battery.

There are some which you an set the amps and has built in load and fan/heat sink to dissipate the heat, but those are LIMITED to 185watts of draw.

I would give this one: 3 gobi rating.

How to use this:
Just connect it in between your LOAD (inverter in my case) and the battery.
 

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Wayne

Administrator
Staff member
6554 watts is a lot of power! I'll bet you can't draw that much through it for very long. Looks pretty useful and for $10 it's a great value.
 
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