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My guess was you had it wired wrong and it wasn’t turning off the charger so you overcharged them multiple times. They could all be damaged which will appear as lower capacity. If you have a way to discharge them one at a time and then charge them one at a time and measure the amp hours in and out you could determine if any were damaged. Personally I think battery balances shorten the life of your cells anyway. I don’t know of a simple solution to your problem.
 

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Here is what I came up with to find the problem I first checked the cells voltages. I jacked up the rear wheels and put them on jack stands then I put the truck in 5th gear and had someone run the accelerator peddle until the BMS alarm started buzzing I was watching the BMS boards on the battery cells to see if one would go out. One did go out and I checked the voltage while it was out and it sagged down to 2.51v before the test it was 3.34v. I checked an hour after the test and the voltage was back up to 3.34v so I am assuming that battery cell is bad but why? This will be the 5th battery I have had to replace.

There may not be a problem with your "low" five cells. CALB's will self-discharge from storage. It only takes a couple of months and some cells can self discharge to 50% capacity.


Easy fix, though. Just charge each cell individualy until 3.500 volts, 3.550 volts, or whatever cutoff top voltage you wish. Some cells may take a day to charge up if charging at a low current.


I have CALB SE blue and CALB CA gray cells and have a couple of stinkers that require a 5 amp charge; those cells may take 10 hours to charge.


The term for the top off charge is: TOP BALANCING.


Been there, done that. Usually the stinker cells recover to full capacity. I do this every couple of months.
 

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+1 on what paul said.

if you ever over-discharged the cells (took them too low), then the damage was done. Some may take longer to manifest than others, but they have been bit and will die.

From what i have seen and read about that chemistry i wouldn't want to charge above 3.34 nor discharge below 3.0--there is no real energy available outside that band, and the risk of damage is too high.

just my 2¢, ymmv
 

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Discussion Starter · #24 ·
There may not be a problem with your "low" five cells. CALB's will self-discharge from storage. It only takes a couple of months and some cells can self discharge to 50% capacity.


Easy fix, though. Just charge each cell individualy until 3.500 volts, 3.550 volts, or whatever cutoff top voltage you wish. Some cells may take a day to charge up if charging at a low current.


I have CALB SE blue and CALB CA gray cells and have a couple of stinkers that require a 5 amp charge; those cells may take 10 hours to charge.


The term for the top off charge is: TOP BALANCING.


Been there, done that. Usually the stinker cells recover to full capacity. I do this every couple of months.
While I have charged with the onboard charger once or twice the majority of the time probably four or five times I charged with a top balancing charger and charged each cell independently to about 3.45v + or - .o5mv. I have rechecked the other five batteries and one is just dead the others when they are in use the BMS LED light goes out and alarms even when they have just been charged and show full capacity. After reading all your replies I am now wondering whether I will be chasing around one cell after another always finding the next weakest link in the pack. One thing that I did do was when a cell failed I replaced a blue cell SE with a gray cell CA three in total because I was told that it wouldn't hurt anything. I bought the new cells from CALB and at the time they said it wouldn't hurt anything now they tell me I shouldn't have done that. They don't make the blue SE cells anymore and at the time as I said they said it wouldn't hurt anything now they have a new sales person and she says differently so I don't know what to do now.
 

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As I said you need to characterize your pack to know what you have before you can proceed with confidence. A lot of work I know. The issue with replacing new cells with old cells is that the voltage will drop faster on old cells because of capacity fade leading to unbalances in the pack. If you have the BMS set up to balance the cells at the top then that's probably as good as it gets. The low voltage alarm should keep you from loosing more cells depending on the voltage it uses to trigger. If you have a high voltage and low voltage alarm i don't see how you would continue to loose cells.
 

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+1 on what paul said.

if you ever over-discharged the cells (took them too low), then the damage was done. Some may take longer to manifest than others, but they have been bit and will die.

From what i have seen and read about that chemistry i wouldn't want to charge above 3.34 nor discharge below 3.0--there is no real energy available outside that band, and the risk of damage is too high.

just my 2¢, ymmv
Not exactly the same thing Kenny..... That is a discharge curve you need to analyze a charge curve. It has been a while since I looked at this but to my recollection when charging you charge at CC until that voltage is reached and then CV or hold the voltage till some current cutoff. It's really the CV mode that one can avoid and voltage is not really an issue. You can calculate the energy under the curve and see that it's maybe 5% of the total you put in the cell. I charged mine to 3.65V and then cutoff the charger skipping the CV mode altogether. There are several papers out where they experimented with different voltages .... i might still have them if you want to read them. Also, in my own experiments that during the CV mode the temperature in the cell rises dramatically in a short period. If memory serves it was a 50% temp rise in 5 minutes up to 50 C or something before I shut it down.
 

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While I have charged with the onboard charger once or twice the majority of the time probably four or five times I charged with a top balancing charger and charged each cell independently to about 3.45v + or - .o5mv. I have rechecked the other five batteries and one is just dead the others when they are in use the BMS LED light goes out and alarms even when they have just been charged and show full capacity. After reading all your replies I am now wondering whether I will be chasing around one cell after another always finding the next weakest link in the pack. One thing that I did do was when a cell failed I replaced a blue cell SE with a gray cell CA three in total because I was told that it wouldn't hurt anything. I bought the new cells from CALB and at the time they said it wouldn't hurt anything now they tell me I shouldn't have done that. They don't make the blue SE cells anymore and at the time as I said they said it wouldn't hurt anything now they have a new sales person and she says differently so I don't know what to do now.

Good to know you're individually charging each cell. Next step is to do a load test on the whole pack. First step is to bulk charge the pack as usual until the bulk charger shuts off. Then use the individual charger on each cell until you reach your 3.45 volts. This will be the starting point= all cells fully charged.


To start the load test, purchase one 2000 watt, 120 volt water heater element at the hardware store. Connect two #14 wires to the element and to the positive and negative 144 volts AFTER the power connector. Place the water heater element in a 5-30 gallon PLASTIC bucket and fill with water. Leave the garden hose running slowly into the bucket, orherwise the water will boil and the element will burn open.


Turn on the ignition and wait until the first cell hits LV via the Mini BMS. Verify the voltage of that cell with your DVM. Note this voltage. Shut off the ignition and disconnect the copper inter-conects to this low cell and bypass the connections that used to go to this cell with a #14 wire with 5/16" ring lugs and a spare nut and bolt.


Note the AH of your EMeter/ JLD404 when the cell hits LV. Turn ignition back on and continue until the next cell hits LV and note the cell number and AH. Then bypass this second cell with the wire jumper and continue.


In a perfect world, ALL cells will provide 100 AH. But, in the real world, your cells will probably hit LV at different AH. It will take many hours to obtain the data and jumper out the cell connections, but after the test the data will show the capacity of each cell. You can then make a decision of which cells are bad and what to do about it.


Blue vs. Gray cells would replace blue cells with more blue cells, but since the blue cells were discontinued about 5 years ago, the isn't much choice but to use gray cells for replacement.


I have performed this load with both the blue cells in one of my conversions and the gray cells in the other conversion. The data will allow you to move on. Without the load test, you're pixxing into the wind.


Been there, done that since 1982 on EV conversions.
 

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Discussion Starter · #28 ·
Wow I am impressed by the detailed instructions you posted. I foolish thought all the hard work was done when I pulled the IC engine and the wiring all the batteries controller BMS and other mechanical work. So I am not spinning my wheels or in this case so I can spin my wheels I am going to ask you some more questions. The #14 wire you are talking about is that stranded wire or solid wire? You state that I am suppose to connect the positive and negative 144v after the power connector what do you mean by that and where would I do that? Next I have never heard of EMeter/JLD 404 where do I get one how much does it cost and how do I hook it up? I am guessing it measure the amp hour of each cell but I am unsure about the wiring of it and in particular the jumping of the cells. It will take me some time to gather up all the stuff you said I need and to preform the test so I guess we will be posting back and forth for a while. I do appreciate your help and all the information you gave me but I was wondering is this a normal thing having to check AH on new cells or at least very little used cells?
 

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Discussion Starter · #29 ·
Good to know you're individually charging each cell. Next step is to do a load test on the whole pack. First step is to bulk charge the pack as usual until the bulk charger shuts off. Then use the individual charger on each cell until you reach your 3.45 volts. This will be the starting point= all cells fully charged.


To start the load test, purchase one 2000 watt, 120 volt water heater element at the hardware store. Connect two #14 wires to the element and to the positive and negative 144 volts AFTER the power connector. Place the water heater element in a 5-30 gallon PLASTIC bucket and fill with water. Leave the garden hose running slowly into the bucket, orherwise the water will boil and the element will burn open.


Turn on the ignition and wait until the first cell hits LV via the Mini BMS. Verify the voltage of that cell with your DVM. Note this voltage. Shut off the ignition and disconnect the copper inter-conects to this low cell and bypass the connections that used to go to this cell with a #14 wire with 5/16" ring lugs and a spare nut and bolt.


Note the AH of your EMeter/ JLD404 when the cell hits LV. Turn ignition back on and continue until the next cell hits LV and note the cell number and AH. Then bypass this second cell with the wire jumper and continue.


In a perfect world, ALL cells will provide 100 AH. But, in the real world, your cells will probably hit LV at different AH. It will take many hours to obtain the data and jumper out the cell connections, but after the test the data will show the capacity of each cell. You can then make a decision of which cells are bad and what to do about it.


Blue vs. Gray cells would replace blue cells with more blue cells, but since the blue cells were discontinued about 5 years ago, the isn't much choice but to use gray cells for replacement.


I have performed this load with both the blue cells in one of my conversions and the gray cells in the other conversion. The data will allow you to move on. Without the load test, you're pixxing into the wind.


Been there, done that since 1982 on EV conversions.
Hey I have been thinking and was wondering if the fuel gauge I bought would work. I believe it is an Expert Pro and I have been reading up on the one you recommended the Emeter / JLD 404 and it seems like what I have does pretty much the same thing. I will post some pictures of what I have so you can see what I am talking about and if it would work.
 

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Hey I have been thinking and was wondering if the fuel gauge I bought would work. I believe it is an Expert Pro and I have been reading up on the one you recommended the Emeter / JLD 404 and it seems like what I have does pretty much the same thing. I will post some pictures of what I have so you can see what I am talking about and if it would work.
Yes, your Expert Pro is the newer version of the E Meter. The original E Meter had a LED display, the Expert Pro has a LCD display. Both units will count and display AH during driving (-) and charging (+). The old E Meter also displays watt hours, so watt hours/mile can be calculated knowing your odometer reading.

Any wiring in a moving vehicle shall be stranded copper. Solid copper wire is at the bottom of the barrel and is used mostly in residential construction. A common stranded wire to use for the load test heating element is THHN stranded, 14 gauge, available at Home Depot in small rolls.

Start your test fully charged, the Exper Pro should indicate 0 AH. As the discharge starts, the Pro will indicate minus AH. If the water heater element draws 15 amps (as shown in the Pro in the amperes mode) for one hour, the Pro will indicate -15 AH. In two hours, the Pro will indicate -30 AH. When charging, say at 10 amps for one hour, the Pro will reverse 10 AH in for a reading of -20 AH. Twenty more AH from your charger will indicate 0 AH, which is a full pack. This DOES NOT indicate individual cell AH, just the whole pack. That's why you have to monitor your Mini BMS and Pro and note which cell craps out at what AH.

Mistake in previous post: The water heater element connects to the switches side of the power CONTACTOR, not the connector.
 

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Here's the JLD404 meter showing -1.293 AH. Also displays pack voltage, battery amps, and elapsed time in a super bright blue LED display that can be seen from the back seat in bright sunlight wearing dark sun glasses. So cool. About $75. :)

Picture taken just after charger shut off at first cell = 3.500 volts (rising) HV. Russco Charger and Cell Log 8 BMS system latches off charger on charge and energizes a buzzer during driving = 2.750 volts on first cell to hit LV (decreasing).
 

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Discussion Starter · #32 ·
Here's the JLD404 meter showing -1.293 AH. Also displays pack voltage, battery amps, and elapsed time in a super bright blue LED display that can be seen from the back seat in bright sunlight wearing dark sun glasses. So cool. About $75. :)

Picture taken just after charger shut off at first cell = 3.500 volts (rising) HV. Russco Charger and Cell Log 8 BMS system latches off charger on charge and energizes a buzzer during driving = 2.750 volts on first cell to hit LV (decreasing).
I been experimenting around trying to understand what is going on with the battery pack so I have taken pictures of the battery pack at rest and when the BMS alarms. At rest meaning the motor is not running just the ignition switch is turned on I have 0 A and 99.9 AH. When I engage the motor and run it to the point the BMS system alarms I have +85.7 A and 100.0 AH. I would think as the Amp draws gets greater amount of current the Amp Hours would go down. The speedometer was around 60 mph when the BMS alarmed I would think even if one battery craps out it would show in the AH reading.
 

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I been experimenting around trying to understand what is going on with the battery pack so I have taken pictures of the battery pack at rest and when the BMS alarms. At rest meaning the motor is not running just the ignition switch is turned on I have 0 A and 99.9 AH. When I engage the motor and run it to the point the BMS system alarms I have +85.7 A and 100.0 AH. I would think as the Amp draws gets greater amount of current the Amp Hours would go down. The speedometer was around 60 mph when the BMS alarmed I would think even if one battery craps out it would show in the AH reading.
You may be displaying the wrong screen on your Expert Pro.

For more information, go to You Tube and search: "Expert Pro Battery Monitor". Dozens of videos on the Pro.
 

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Discussion Starter · #34 ·
You may be displaying the wrong screen on your Expert Pro.

For more information, go to You Tube and search: "Expert Pro Battery Monitor". Dozens of videos on the Pro.
I made a mistake my gauge is not an Expert Pro it is instead a clean power auto gauge which is very similar to the Expert in looks and in performance although it would appear they are out of business by their website. In the manual it say's that it monitor ah amp watt volts in a split screen so you don't need to keep switching back and forth.
 

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Discussion Starter · #35 ·
Good to know you're individually charging each cell. Next step is to do a load test on the whole pack. First step is to bulk charge the pack as usual until the bulk charger shuts off. Then use the individual charger on each cell until you reach your 3.45 volts. This will be the starting point= all cells fully charged.


To start the load test, purchase one 2000 watt, 120 volt water heater element at the hardware store. Connect two #14 wires to the element and to the positive and negative 144 volts AFTER the power connector. Place the water heater element in a 5-30 gallon PLASTIC bucket and fill with water. Leave the garden hose running slowly into the bucket, orherwise the water will boil and the element will burn open.


Turn on the ignition and wait until the first cell hits LV via the Mini BMS. Verify the voltage of that cell with your DVM. Note this voltage. Shut off the ignition and disconnect the copper inter-conects to this low cell and bypass the connections that used to go to this cell with a #14 wire with 5/16" ring lugs and a spare nut and bolt.


Note the AH of your EMeter/ JLD404 when the cell hits LV. Turn ignition back on and continue until the next cell hits LV and note the cell number and AH. Then bypass this second cell with the wire jumper and continue.


In a perfect world, ALL cells will provide 100 AH. But, in the real world, your cells will probably hit LV at different AH. It will take many hours to obtain the data and jumper out the cell connections, but after the test the data will show the capacity of each cell. You can then make a decision of which cells are bad and what to do about it.


Blue vs. Gray cells would replace blue cells with more blue cells, but since the blue cells were discontinued about 5 years ago, the isn't much choice but to use gray cells for replacement.


I have performed this load with both the blue cells in one of my conversions and the gray cells in the other conversion. The data will allow you to move on. Without the load test, you're pixxing into the wind.


Been there, done that since 1982 on EV conversions.
I just got done with charging each cell one at a time to about an average of 3.345v even though I had the charger set to 3.50v I let the cells rest for forty-eight hours before recording the voltage (at the time right after the charge the voltage was around 3.352v) Now I want to make sure how to connect the 2000watt, 120v water heater element to the pack to do load test, as I understand it you want me to connect the two leads to the water heater element to the contactor is that correct?
 

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