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Brand new, but tragically dead Trojans

Netsua

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Jul 22, 2021
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105
I’ve read a million threads on reviving old/dead batteries... but none on brand new dead batteries.

Yes, I purchased 24 Trojan t105s as a backup battery bank. I had some family emergencies and they have been sitting... almost 5 months.

I have several different chargers, so I can charge at pretty much any voltage or current level. But I don’t know what setup would be best to charge these brand new... but also dead batteries.
 
Don't wait another hour. Get them on charge to 7.4 volts per battery immediately. You can connect in series or parallel to get the voltage correct.
Get busy.
 
Don't wait another hour. Get them on charge to 7.4 volts per battery immediately. You can connect in series or parallel to get the voltage correct.
Get busy.
I should have elaborated... my plan was to series parallel them into 3 strings at 48v total. I completed that this evening. My plan was to get them charging tomorrow - but I’ve yet to run into anyone as stupid as I am, so I don’t know if I should attempt to desulphate right away, low and slow them with 20 amps, or what.
 
what is dead? Voltage? SG?
To be honest... I planned on charging them tomorrow either way. In order to allow myself to sleep tonight, I did not test.

I think it’s safe to assume they are quite dead though.
 
I should have elaborated... my plan was to series parallel them into 3 strings at 48v total. I completed that this evening. My plan was to get them charging tomorrow - but I’ve yet to run into anyone as stupid as I am, so I don’t know if I should attempt to desulphate right away, low and slow them with 20 amps, or what.
Get the voltage up to 7.4 or 59.2 for the string of 8 asap. I would put at least 100 amps into the set. No reason to baby these batteries. Lead-acid likes to be charged. OK to float them overnight at 54.4 once they are mostly charged. Equalize tomorrow.

Or maybe they are not as dead as you think?
 
Get the voltage up to 7.4 or 59.2 for the string of 8 asap. I would put at least 100 amps into the set. No reason to baby these batteries. Lead-acid likes to be charged. OK to float them overnight at 54.4 once they are mostly charged. Equalize tomorrow.
Thank you. This is exactly what I needed.
 
First, get a battery hydrometer and test each one. Then put each one on a 6V charger and fully equalize each cell. Take notes on what the hydrometer says. Match up the batteries into 48V strings keeping the best batteries into one string, the second best into another, etc. Then test each string.

Frankly, I have seen batteries sit way longer and be OK.
 
Likely salvageable.

Just do what this says:


and download the appropriate datasheet for your battery for voltage, SG, etc., references:


Short version:
  1. Fully charge INDIVIDUALLY per instructions (pages 16-18).
  2. Check SG of all 3 cells (page 25).
  3. If SG is below 1.277 or variation between 3 cells is > 0.03, conduct equalization cycle in accordance with instructions (page 20).
Given that they are new, it's likely they'll fully recover. I've left cheap 5 year old batteries sitting for months, and they recover after 1-2 equalization cycles. They are much lower quality than Trojan.
 
Likely salvageable.

Just do what this says:


and download the appropriate datasheet for your battery for voltage, SG, etc., references:


Short version:
  1. Fully charge INDIVIDUALLY per instructions (pages 16-18).
  2. Check SG of all 3 cells (page 25).
  3. If SG is below 1.277 or variation between 3 cells is > 0.03, conduct equalization cycle in accordance with instructions (page 20).
Given that they are new, it's likely they'll fully recover. I've left cheap 5 year old batteries sitting for months, and they recover after 1-2 equalization cycles. They are much lower quality than Trojan.
Well that’s a bummer. They’ve been sitting around individually for 5 months... I just series/paralleled them last night lol. I thought they needed to be treated as a single unit from day 1.
 
Well that’s a bummer. They’ve been sitting around individually for 5 months... I just series/paralleled them last night lol. I thought they needed to be treated as a single unit from day 1.

1635338358894.png

For expediency, paralleling them in smaller groups for charging would be fine. Series charging should be avoided until the batteries are all fully charged.
 
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Thoughs battery are lead-antimony alloy plate with about 15% per month self discharge rate. If they started out fully charged there is hope although there will be some sulfation to deal with.

Equalization will help breaking up sulfation but need to be careful not to over do it. Do it in stages of a couple of hours each time with few hours between to cool down, then check SG levels. Be ready to add water to keep above plates.

You will not likely be able to bring SG up to full levels. Some sulfated lead will break off and drop to bottom of cell. This is good as it re-exposes plate surface but the lead-sulfate that breaks off carries sulphur away that no longer will converter water in electrolyte back to sulfuric acid resulting in reduced SG level. Trick on equilization is knowing when to stop when SG levels do not improve with additional equilization.
 
Thoughs battery are lead-antimony alloy plate with about 15% per month self discharge rate. If they started out fully charged there is hope although there will be some sulfation to deal with.

Equalization will help breaking up sulfation but need to be careful not to over do it. Do it in stages of a couple of hours each time with few hours between to cool down, then check SG levels. Be ready to add water to keep above plates.

You will not likely be able to bring SG up to full levels. Some sulfated lead will break off and drop to bottom of cell. This is good as it re-exposes plate surface but the lead-sulfate that breaks off carries sulphur away that no longer will converter water in electrolyte back to sulfuric acid resulting in reduced SG level. Trick on equilization is knowing when to stop when SG levels do not improve with additional equilization.

Good addendum to the Trojan guidance. Speaking to the "cool down" portion, while Trojan doesn't mention anything specific, other manufacturers have a prescribed temperature limit. When it's not specified, I prefer to use 100-110°F.
 
View attachment 70364

For expediency, paralleling them in smaller groups for charging would be fine. Series charging should be avoided until the batteries are all fully charged.
Apparently I’ve been doing it incorrectly for a few years... all my chargers are 36/48V.

Anyone have a recommendation for a good 6V to make this happen? Amazon had several Schumaker chargers that I can get Same Day if I’m fast.

Thank you all
 
I have several different chargers, so I can charge at pretty much any voltage or current level. But I don’t know what setup would be best to charge these brand new... but also dead batteries.


Apparently I’ve been doing it incorrectly for a few years... all my chargers are 36/48V.

These two statements are incongruous. Your first statement strongly implies that charging a 6V battery and high current is readily within your ability. Your subsequent statement clearly indicates you can ONLY charge 36/48V. Please consider that those trying to provide advice will benefit from better information provided on your part.

Given that you have 5400Ah of 6V capacity, you need to consider that in your charger selection. A 20A charger will take >270 hours of charging. This may be burdensome.

Given the circumstances, it may make more sense to charge in series; HOWEVER, it is critical that you monitor the voltage of EACH battery in series to insure it does not exceed the recommended absorption voltage significantly, and they never exceed. I would use your highest amperage 36V charger and configure the bank as 4P6S to minimize the number of voltage elements you have to monitor.

When constructing your bank for charging, ensure you use best practices as much as possible:


Once you are equalizing, it would likely be best to use chargers on single 6S or 8S strings, so you can be confident that all cells in series are getting the same current.

Again, monitoring the individual 6V during series charging is very important. The highest voltage battery is your limiting factor. If you allow it's voltage to go too high, you will damage it.
 
These two statements are incongruous. Your first statement strongly implies that charging a 6V battery and high current is readily within your ability. Your subsequent statement clearly indicates you can ONLY charge 36/48V. Please consider that those trying to provide advice will benefit from better information provided on your part.

Given that you have 5400Ah of 6V capacity, you need to consider that in your charger selection. A 20A charger will take >270 hours of charging. This may be burdensome.

Given the circumstances, it may make more sense to charge in series; HOWEVER, it is critical that you monitor the voltage of EACH battery in series to insure it does not exceed the recommended absorption voltage significantly, and they never exceed. I would use your highest amperage 36V charger and configure the bank as 4P6S to minimize the number of voltage elements you have to monitor.

When constructing your bank for charging, ensure you use best practices as much as possible:


Once you are equalizing, it would likely be best to use chargers on single 6S or 8S strings, so you can be confident that all cells in series are getting the same current.

Again, monitoring the individual 6V during series charging is very important. The highest voltage battery is your limiting factor. If you allow it's voltage to go too high, you will damage it.

These two statements are incongruous. Your first statement strongly implies that charging a 6V battery and high current is readily within your ability. Your subsequent statement clearly indicates you can ONLY charge 36/48V. Please consider that those trying to provide advice will benefit from better information provided on your part.

Given that you have 5400Ah of 6V capacity, you need to consider that in your charger selection. A 20A charger will take >270 hours of charging. This may be burdensome.

Given the circumstances, it may make more sense to charge in series; HOWEVER, it is critical that you monitor the voltage of EACH battery in series to insure it does not exceed the recommended absorption voltage significantly, and they never exceed. I would use your highest amperage 36V charger and configure the bank as 4P6S to minimize the number of voltage elements you have to monitor.

When constructing your bank for charging, ensure you use best practices as much as possible:


Once you are equalizing, it would likely be best to use chargers on single 6S or 8S strings, so you can be confident that all cells in series are getting the same current.

Again, monitoring the individual 6V during series charging is very important. The highest voltage battery is your limiting factor. If you allow it's voltage to go too high, you will damage it.
When I first mentioned that I could charge at pretty much any voltage, I never considered that 6V would even be an option/possibility. I have two magnum inverter/chargers at 48V, and AIMS inverter/charger at 48V, an AIMS 36/48V Charger, and several 12V chargers. I've never even looked for a 6V charger - and they seem to be relatively hard to find with high amps.

I appreciate your thorough response - digesting now.

For further clarity, my original plan was to charge all 28 batteries at once. I was essentially asking if it would be better to charge them all (simultaneously) at high current or lower/slower. This advice is pretty contrary to that plan, and I’m definitely wanting to follow.
 
When I first mentioned that I could charge at pretty much any voltage, I never considered that 6V would even be an option/possibility. I have two magnum inverter/chargers at 48V, and AIMS inverter/charger at 48V, an AIMS 36/48V Charger, and several 12V chargers. I've never even looked for a 6V charger - and they seem to be relatively hard to find with high amps.

I appreciate your thorough response - digesting now.

"several 12V chargers" - would be good for charging multiple 2S strings.

I have more charging capability than most. I can charge anything from 1.2V to 48V with a wide range of possible current (20A minimum at all voltages), so my perspective is skewed. To give you an idea of my skewed perspective, I could INDIVIDUALLY charge 42 6V batteries to whatever voltage I want at 20A, and I have several other chargers I'm not considering. Yes. I have spent several thousand dollars on chargers. Don't be me.

I would look at deploying as many chargers as possible to as few paralleled batteries as possible for the initial charge. Plan to spend a whole day scrambling between 6V checking voltages. Hopefully, given they are new, there will be little to no variation, and this may be easier than it sounds, but as mentioned above, this is the time where you would sort batteries into "bins" of high and low voltage, so you can match similar voltages for series charging.
 
"several 12V chargers" - would be good for charging multiple 2S strings.

I have more charging capability than most. I can charge anything from 1.2V to 48V with a wide range of possible current (20A minimum at all voltages), so my perspective is skewed. To give you an idea of my skewed perspective, I could INDIVIDUALLY charge 42 6V batteries to whatever voltage I want at 20A, and I have several other chargers I'm not considering. Yes. I have spent several thousand dollars on chargers. Don't be me.

I would look at deploying as many chargers as possible to as few paralleled batteries as possible for the initial charge. Plan to spend a whole day scrambling between 6V checking voltages. Hopefully, given they are new, there will be little to no variation, and this may be easier than it sounds, but as mentioned above, this is the time where you would sort batteries into "bins" of high and low voltage, so you can match similar voltages for series charging.
It was mentioned above that I should not charge in strings - that’s the reason I wasn’t planning on using my 12v chargers. Do you disagree with that?

EDIT: I'm not opposed to buying some 6V chargers also. Better than letting my batteries get worse. Any opinion on this:

 
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It was mentioned above that I should not charge in strings - that’s the reason I wasn’t planning on using my 12v chargers. Do you disagree with that?

You will have to charge in strings at anything but 6V. Given that you do not have a 6V charger, and you have a MASSIVE amount of 6V capacity that would take WEEKS to charge at 6V, series charging with the aforementioned monitoring of 6V is the reasonable option.

There's best and then there's practical.
 
You will have to charge in strings at anything but 6V. Given that you do not have a 6V charger, and you have a MASSIVE amount of 6V capacity that would take WEEKS to charge at 6V, series charging with the aforementioned monitoring of 6V is the reasonable option.

There's best and then there's practical.
Copy. Thank you for clarifying.

I'm more than tempted to just charge all 24 in series parallel through the two magnums in parallel and be done with it... but I will resist.
 
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