32 Ah from one 1.5Ah Makita battery cell

[marty]

Doctorbass wrote:
Konion Makita LiMn battery care and feeding by Doctorbass
http://endless-sphere.com/forums/viewtopic.php?f=14&t=27707

x
18 is for 18mm diameter and 650 for 65.0mm lengh


They come in different pack on the market:

The 18650V are used in:
-The BL1830 makita pack of 18V 3.0Ah
-The BionX electric bike battery of 24V and 37V 9.6Ah

The 18650VT are used in:
-The BL1815 makita pack of 18V 1.5Ah ( but they have 1.3Ah real)
-The Bosh 36V slim and fatpack


Here are their specs:

18650V: ( the most popular for ebikes)
( same as the Sanyo’s UR18650W)

-Voltage range: 3.0 to 4.2V
-Nominal voltage 3.7V
-Capacity: 1500mAh(10C) to 1600mAh(1C)
-Max Discharge C rate: 10C ( 15-16A)
-Max Charge C-rate: 1.5 to 2C depending on the cooling
-Cycle life: 700 cycles to 75% initial capacity ( from BMZ manufacture)
-Cycle life claimed by Makita: 1200 cycles
-Internal resistance 30miliohm per cells
-Released in 2005... still existing in 2011



18650VT:

-Voltage range: 3.0 to 4.1 or 4.2V
-Nominal voltage 3.76V
-Capacity: 1030mAh(10C), 1080mAh, ( 1C) to 1300mAh(0.1C)
-Max Discharge C rate: 15C ( 17-20A)... and 30A for 30 sec
-Max Charge C-rate: 3C depending on the cooling
-Cycle life: 500 cycles to 90% of initial capacity, at 2A discharge ( from BMZ manufacture)
-Cycle life claimed by Makita: 1200 cycles
-Internal resistance :initial is 25 miliohm ( 26-28 miliohm of used cells)
-Gravimetric energy94 Wh/kg
-Released in 2005... still existing in 2011

x

I have been playing with and learning about West Mountain Radio CBA III - Computerized Battery Analyzer. As a experiment I tried draining a cell to .8V I realize that this will kill the cell. You can call me the battery murderer boy.

1500 mAh is 1.5 Ah correct?

Noticed that when voltage gets low the graph seems to almost go in a flat line. Amp Hours just go on and on. Why is this? Have I discovered a battery that never runs out :?


Description: 1 Li-ion cell, 1.0 Ah @ 2.00A
Started At: 4/26/2012 4:59 PM
Discharge Rate: 2.00 A
Starting Voltage: 1.83 V
Ending Voltage: 0.89 V [Stoped the test because after 16 hours I got tired of looking at it]
Total Time (hh:mm:ss): 16:01:07
Tested Capacity: 32.038 Ah

Lumps in the graph line are caused by bumping the table, moving the cell, wiggling the alligator clips.

 

[amberwolf]

Once the voltage is below the usable (or recoverable) level, it's irrelevant what "Ah" you can draw from a cell (mostly because with many cells, you can't recharge it afterward, and with most systems you can't practically use a voltage below some level).

BTW, what was the actual Amp load on the battery, and how long was the test?

 

[marty]

Mystery solved. CBA III - Computerized Battery Analyzer was not drawing enough amps. Called West Mountain Radio tech guy. He said to check the fuse and if fuse good, measure amps. Checked fuse, fuse good. Measured amps, all OK. CBA is working fine now. Don't know what the problem was? Suspect it was something similar to turning a computer off and on again to get rid of demons causing trouble.

 

[Doctorbass]

Mystery solved. CBA III - Computerized Battery Analyzer was not drawing enough amps. Called West Mountain Radio tech guy. He said to check the fuse and if fuse good, measure amps. Checked fuse, fuse good. Measured amps, all OK. CBA is working fine now. Don't know what the problem was? Suspect it was something similar to turning a computer off and on again to get rid of demons causing trouble.

I had this type of problem... it was due to CBA software problem... i reboted the computer nad it cameback to normal :wink:

Doc

 

[chilledoutuk]

im sorry that thing is a piece of crap why buy for $149.95 what is basically a battery discharger something that is built in to most decent battery chargers like the intellipeak ice.

Regardless on chargers like the intellipeak ice and ichargers you can cycle cells and see exactly what rate there discharging at.