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sikeston34m · 04:55 PM

The 150C rating is ludicrous considering current technology.

Let's just run some numbers. Simple Math.

We have a 150C 6500 mah Lithium Polymer cell.

At a 975 amp discharge rate, each cell is capable of 4095 watts of power.

If we discharge our fully charged cell at the 150C discharge rate, it will be fully drained in 24 seconds. (If anyone is interested in the formula for calculating any of this, I'll post them up.)

I am a Refrigeration/Maintenance Engineer for a Distribution Center here in Missouri.

It's very common for me to deal with Techs and Sales Reps from industrial battery companies such as IBP and Deka.

Batteries have always fascinated me, so I ask alot of questions and stick my head in the books.

Here is a comparison for you. The battery in question is a 36 volt 1000ah lead acid Industrial Truck battery weighing in at 2850 pounds.

Each main power lead is about as big around as a fat cigar. Cross sectional area comparable to a Nickle.

It takes a well co-ordinated forklift driver about 6 hours to drain one of these batteries. Obviously alot of energy.

The question that I posed to IBP and Deka Techs:

What is the maximum discharge rate limit before damage occurs?

Answer: Right around 750 amps. It is at this point, it blows the jumper bars off the cells.

Jumper Bars are the intercell connections. Each unit is made up of 18 - 2 volt cells connected in series. Total of 36 volts.

They use pairs of jumper bars to jump from one cells positive posts to the next neighboring set of negative posts.

EACH jumper bar is around 2" wide and 1/2" thick and about 6" long. They are made of lead.

I've witnessed several accidents where the main power leads were crush/pinched to the point where a dead short condition occured.

Never have I seen the jumper bars blow off, but a battery this size can discharge enough amps to snap 1/0 leads in a shower of sparks. I have seen this happen. It's quite scarey.

Now, back to the 150C rating. We are going to discharge a 6500mah Lipo Pack at 975 amps continuous?

How are we going to test that since the entire discharge process will only last 24 seconds?

These numbers are off the scale and highly impossible IMO.

	(#1)
sikeston34m RC-Monster Brushless Offline Posts: 2,085 Join Date: Sep 2007	10.15.2010, 04:52 PM The 150C rating is ludicrous considering current technology. Let's just run some numbers. Simple Math. We have a 150C 6500 mah Lithium Polymer cell. At a 975 amp discharge rate, each cell is capable of 4095 watts of power. If we discharge our fully charged cell at the 150C discharge rate, it will be fully drained in 24 seconds. (If anyone is interested in the formula for calculating any of this, I'll post them up.) I am a Refrigeration/Maintenance Engineer for a Distribution Center here in Missouri. It's very common for me to deal with Techs and Sales Reps from industrial battery companies such as IBP and Deka. Batteries have always fascinated me, so I ask alot of questions and stick my head in the books. Here is a comparison for you. The battery in question is a 36 volt 1000ah lead acid Industrial Truck battery weighing in at 2850 pounds. Each main power lead is about as big around as a fat cigar. Cross sectional area comparable to a Nickle. It takes a well co-ordinated forklift driver about 6 hours to drain one of these batteries. Obviously alot of energy. The question that I posed to IBP and Deka Techs: What is the maximum discharge rate limit before damage occurs? Answer: Right around 750 amps. It is at this point, it blows the jumper bars off the cells. Jumper Bars are the intercell connections. Each unit is made up of 18 - 2 volt cells connected in series. Total of 36 volts. They use pairs of jumper bars to jump from one cells positive posts to the next neighboring set of negative posts. EACH jumper bar is around 2" wide and 1/2" thick and about 6" long. They are made of lead. I've witnessed several accidents where the main power leads were crush/pinched to the point where a dead short condition occured. Never have I seen the jumper bars blow off, but a battery this size can discharge enough amps to snap 1/0 leads in a shower of sparks. I have seen this happen. It's quite scarey. Now, back to the 150C rating. We are going to discharge a 6500mah Lipo Pack at 975 amps continuous? How are we going to test that since the entire discharge process will only last 24 seconds? These numbers are off the scale and highly impossible IMO. Last edited by sikeston34m; 10.15.2010 at 04:55 PM.