I have a few threads going right now about a pair of T-105's i recently purchased. I purchased two of them brand new. One of them was 6.32 volts and one of them 6.37 volts when i measured them back at the shop. It was suggested that i charge them in parallel before connecting them in series in the boat to equalize the charge between the two. I bought a 6v/12v charger and charged them to equalize the charge. When i was charging them i did notice a slight hydrogen sulfide smell coming from one of them. Due to my inexperience i didnt pay much attention. When i installed them in the boat they were both fully charged and within .02 voltage between the two batteries. I turned on my charger for about ten minutes or so (Sterling Pro Charge Ultra) to set the custom voltages. While they were receiving charge one or both of them was off-gassing hydrogen sulfide.
Over this weekend i took the time to run the batteries down to help break them in but also to see how they react from a deep state of discharge when being charged, to see if the info tells me anything. I honestly dont know enough about batteries yet to interpret the results or if the information means anything at all. I know there are some very smart people on this board, so in an attempt to maybe learn something or just to get an opinion if the numbers suggest that all is good with the batteries, or maybe one of them is damaged. The batteries are under warranty so if one of them is bad (the reason for the hydrogen sulfide smell?) i'd like to replace it asap.
As i ran down the voltage, the batteries were not draining equally. I didn't record the voltages while i was draining them because it obviously fluctuated quite a bit from the loads, only the voltage of each battery when i stopped. Trojans data sheet specified 5.83 volts was 80% DoD so to play it safe i drew them down to 5.86 / 5.91. Battery A (the battery connected to the chargers positive output) measured 5.86 volts, battery B (connected to the negative) was 5.91 volts.
At this point i immediately started to charge them. The T-105's are 225 Ah batteries. I have my charger set to 50% charge power (30 Amps). I have the charge voltages set to 14.7 bulk / 13.5 float. Trojan recommends 14.8 / 13.5. I have a battery temp wire installed which bumps the voltage up .10 volts at current temps.
I have a remote display for the charger showing what the charger is outputting, and an SG-200 connected at the batteries showing what the batteries are at. All other measurements were taken with a decent quality multi-tester.
Time---------Charger Voltage----------Charger Amps----------Batt. A voltage----------Batt. B voltage-------------Combined voltage-----------SG-200 voltage reading
5:00 PM------------13.5-----------------------------29.9--------------------------6.67-------------------------6.62--------------------------------13.3-------------------------------------13.3
5:30------------------13.5-----------------------------29.9--------------------------6.67-------------------------6.67--------------------------------13.35-----------------------------------13.4
6:00------------------13.6-----------------------------29.9--------------------------6.70-------------------------6.74--------------------------------13.45-----------------------------------13.5
6:30------------------13.7-----------------------------29.9--------------------------6.75-------------------------6.81--------------------------------13.57-----------------------------------13.6
7:30------------------14.1-----------------------------29.9--------------------------6.89-------------------------6.99--------------------------------13.89-----------------------------------13.9
8:15------------------14.6-----------------------------29.3--------------------------7.13-------------------------7.28--------------------------------14.42-----------------------------------14.4
8:45------------------14.6-----------------------------23.0--------------------------7.17-------------------------7.32--------------------------------14.5-------------------------------------14.5
9:45------------------14.6-----------------------------11.1--------------------------7.23-------------------------7.4----------------------------------14.64-----------------------------------14.7
I had to go to bed at this point so unfortunately had to shut down the charger. I know it wasn't finished charging. I will turn it back on, on wednesday when im back at the boat to top up the charge.
During the entire charge process a few things i noticed i'm curious about. The batteries never got to 14.7 volts before the amperage started to drop. Do i have the power of the charger (30 Amps) set too low? With the temp sensor they should have hit 14.8 volts. I figure maybe because of the deep state of discharge they were in maybe had something to do with this.
The cell (plate) that is connected to the positive charge wire (positive post) on battery A was bubbling quite a bit when it got to 14.5 and 14.6 volts range. i could easily hear what sounded like vigerous bubbling. When i popped the cover i noticed a fair amount of bubbles rising but not as bad as it sounded. The other two cells under the caps on the same battery only showed a few bubbles rising here and there. The batteries were all cool to the touch though throughout the entire charge process. Even the cell that was bubbling. Is it normal that the cell/plate connected to the + wire would do this? Interestingly, that battery was at a lower voltage at the time than the other one. I did measure the voltage of the two batteries this morning after they were resting all night. They were pretty close to equal. One was 6.48 and the other 6.50. Also, I never noticed any Hydrogen Sulfide smell this time which is a good sign i guess. I will be curios to see if it comes back when charging from a state of charge that is closer to full.
Anyways, sorry for such a long nerd post. I really like the electrical component on boats but would like to find out if such information has any real value and can help shed some light on the health of the batteries. If i hadn't smelled the Hydrogen Sulfide i woudn't have bothered, but from what iv'e read...its not something to be taken lightly so anything i can do to figure this out i guess is worth it. I really would prefer not to blow up if i can avoid it.
Thanks for reading.
Over this weekend i took the time to run the batteries down to help break them in but also to see how they react from a deep state of discharge when being charged, to see if the info tells me anything. I honestly dont know enough about batteries yet to interpret the results or if the information means anything at all. I know there are some very smart people on this board, so in an attempt to maybe learn something or just to get an opinion if the numbers suggest that all is good with the batteries, or maybe one of them is damaged. The batteries are under warranty so if one of them is bad (the reason for the hydrogen sulfide smell?) i'd like to replace it asap.
As i ran down the voltage, the batteries were not draining equally. I didn't record the voltages while i was draining them because it obviously fluctuated quite a bit from the loads, only the voltage of each battery when i stopped. Trojans data sheet specified 5.83 volts was 80% DoD so to play it safe i drew them down to 5.86 / 5.91. Battery A (the battery connected to the chargers positive output) measured 5.86 volts, battery B (connected to the negative) was 5.91 volts.
At this point i immediately started to charge them. The T-105's are 225 Ah batteries. I have my charger set to 50% charge power (30 Amps). I have the charge voltages set to 14.7 bulk / 13.5 float. Trojan recommends 14.8 / 13.5. I have a battery temp wire installed which bumps the voltage up .10 volts at current temps.
I have a remote display for the charger showing what the charger is outputting, and an SG-200 connected at the batteries showing what the batteries are at. All other measurements were taken with a decent quality multi-tester.
Time---------Charger Voltage----------Charger Amps----------Batt. A voltage----------Batt. B voltage-------------Combined voltage-----------SG-200 voltage reading
5:00 PM------------13.5-----------------------------29.9--------------------------6.67-------------------------6.62--------------------------------13.3-------------------------------------13.3
5:30------------------13.5-----------------------------29.9--------------------------6.67-------------------------6.67--------------------------------13.35-----------------------------------13.4
6:00------------------13.6-----------------------------29.9--------------------------6.70-------------------------6.74--------------------------------13.45-----------------------------------13.5
6:30------------------13.7-----------------------------29.9--------------------------6.75-------------------------6.81--------------------------------13.57-----------------------------------13.6
7:30------------------14.1-----------------------------29.9--------------------------6.89-------------------------6.99--------------------------------13.89-----------------------------------13.9
8:15------------------14.6-----------------------------29.3--------------------------7.13-------------------------7.28--------------------------------14.42-----------------------------------14.4
8:45------------------14.6-----------------------------23.0--------------------------7.17-------------------------7.32--------------------------------14.5-------------------------------------14.5
9:45------------------14.6-----------------------------11.1--------------------------7.23-------------------------7.4----------------------------------14.64-----------------------------------14.7
I had to go to bed at this point so unfortunately had to shut down the charger. I know it wasn't finished charging. I will turn it back on, on wednesday when im back at the boat to top up the charge.
During the entire charge process a few things i noticed i'm curious about. The batteries never got to 14.7 volts before the amperage started to drop. Do i have the power of the charger (30 Amps) set too low? With the temp sensor they should have hit 14.8 volts. I figure maybe because of the deep state of discharge they were in maybe had something to do with this.
The cell (plate) that is connected to the positive charge wire (positive post) on battery A was bubbling quite a bit when it got to 14.5 and 14.6 volts range. i could easily hear what sounded like vigerous bubbling. When i popped the cover i noticed a fair amount of bubbles rising but not as bad as it sounded. The other two cells under the caps on the same battery only showed a few bubbles rising here and there. The batteries were all cool to the touch though throughout the entire charge process. Even the cell that was bubbling. Is it normal that the cell/plate connected to the + wire would do this? Interestingly, that battery was at a lower voltage at the time than the other one. I did measure the voltage of the two batteries this morning after they were resting all night. They were pretty close to equal. One was 6.48 and the other 6.50. Also, I never noticed any Hydrogen Sulfide smell this time which is a good sign i guess. I will be curios to see if it comes back when charging from a state of charge that is closer to full.
Anyways, sorry for such a long nerd post. I really like the electrical component on boats but would like to find out if such information has any real value and can help shed some light on the health of the batteries. If i hadn't smelled the Hydrogen Sulfide i woudn't have bothered, but from what iv'e read...its not something to be taken lightly so anything i can do to figure this out i guess is worth it. I really would prefer not to blow up if i can avoid it.
Thanks for reading.
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