Battery Numbers

[Beau388]

Originally Posted by lwmcguir

https://www.batteryminders.com/tempe...-compensation/

Over heating batteries in hot temps is the biggest issue

For you purist

Voltage test will indicate if you have an anomaly, then you load test

You have more time to waste than I choose to if you always disconnect

If there is no temperature probe attached to a battery post, the converter assumes the converter and batteries are at the same temperature. This can cause overcharging on hot days and lead to out gassing even on VRLA batteries; as well as, grid corrosion. On cool days the converter can undercharge the batteries if the batteries are significantly colder than the converter.. This is harder to predict as some batteries heat up more than others when being charged. It all depends to the internal resistance of the batteries and charging current,

[lwmcguir]

Thanks Beau

[dkoldman]

Originally Posted by Beau388

If there is no temperature probe attached to a battery post, the converter assumes the converter and batteries are at the same temperature. This can cause overcharging on hot days and lead to out gassing even on VRLA batteries; as well as, grid corrosion. On cool days the converter can undercharge the batteries if the batteries are significantly colder than the converter.. This is harder to predict as some batteries heat up more than others when being charged. It all depends to the internal resistance of the batteries and charging current,

Is there an algorithm that shows what it does to the three stages based on ambient temperatures?

I know I do not have temperature probe on my batteries. But I am not convinced that I overcharge my batteries when I use my Progressive Dynamics Intelligent Wizard Converter? Not sure how you undercharge batteries (given they are on aany working charger?) In my case, undercharging is virtually impossible as my batteries never get below 12.5vdc. But It would be nice to know the the differential temperatures between batteries & converter that would necessitate a change in program?

My Batteries and converter are about 6 feet apart, but converter is inside in enclosed wooden box and the batteries are under the steps.

[dkoldman]

Originally Posted by lwmcguir

Thanks Beau

I think I am breaking your rule on this thread. I am getting confused with my intelligence with education

I don't quite follow how you can get true battery readings without disconnection and I have never even heard of temperature being a factor for charging? If I am not edumacated real soon, I will have to call vMax Tank to see why they sold me those expensive AGM batteries knowing full well I had no method for temperature compensation?

[Judge]

Originally Posted by dkoldman

I think I am breaking your rule on this thread. I am getting confused with my intelligence with education

I don't quite follow how you can get true battery readings without disconnection and I have never even heard of temperature being a factor for charging? If I am not edumacated real soon, I will have to call vMax Tank to see why they sold me those expensive AGM batteries knowing full well I had no method for temperature compensation?

Temperature does impact conventional battery charging and performance. My Renogy Solar Controller actually came with a temperature sensor to mount to one of the batteries so it could use the best charging algorithm.

I have LiFePo4 batteries so the temperature sensor is not used in my case.

[Beau388]

Most chemical reactions vary by the temperatures of the reactants. Most reactions are exothermic so battery temperatures rise when charging or discharging. For a much better explanation than I provided try <https://www.prostarsolar.net/support/blog/temperature-effects-on-battery-capacity-and-service-life.html>.
From Parallex
TempAssure™ equipped converters are the only converter systems on the market that can adjust battery voltage based on the temperature in real time.
TempAssure™ was developed in response to the weaknesses in typical “Smart” chargers.
TempAssure™ converters feature temperature Compensated Charging.
TempAssure™ equipped converters are the only converter systems on the market that can adjust the voltage to the batteries based on the temperature in real time.
TempAssure™ was designed with a 4-hour boost mode capped at 14.4 volts followed by a float mode as low as 13 volts.
TempAssure™ features 4 distinct charging voltages that are determined by temperature.
TempAssure™ delivers less battery maintenance, longer battery life, and battery performance out of your batteries.
Parallax Power Supply Temperature Compensated Charging is recommended by every major battery manufacturer.

[Beau388]

Originally Posted by Judge

Temperature does impact conventional battery charging and performance. My Renogy Solar Controller actually came with a temperature sensor to mount to one of the batteries so it could use the best charging algorithm.

I have LiFePo4 batteries so the temperature sensor is not used in my case.

Fortunately most 12 volt LiFePO4 batteries have a BMS to control charging and discharging if the charging voltage is sufficient. Lead acid batteries need a BMS to achieve maximum life and capacity.

[dkoldman]

Originally Posted by Beau388

Most chemical reactions vary by the temperatures of the reactants. Most reactions are exothermic so battery temperatures rise when charging or discharging. For a much better explanation than I provided try <https://www.prostarsolar.net/support/blog/temperature-effects-on-battery-capacity-and-service-life.html>.
From Parallex
TempAssure™ equipped converters are the only converter systems on the market that can adjust battery voltage based on the temperature in real time.
TempAssure™ was developed in response to the weaknesses in typical “Smart” chargers.
TempAssure™ converters feature temperature Compensated Charging.
TempAssure™ equipped converters are the only converter systems on the market that can adjust the voltage to the batteries based on the temperature in real time.
TempAssure™ was designed with a 4-hour boost mode capped at 14.4 volts followed by a float mode as low as 13 volts.
TempAssure™ features 4 distinct charging voltages that are determined by temperature.
TempAssure™ delivers less battery maintenance, longer battery life, and battery performance out of your batteries.
Parallax Power Supply Temperature Compensated Charging is recommended by every major battery manufacturer.

Thank you, my Education has started I have seen enough where I grasp the concept. When I first read it seemed as if it was common knowledge and standard for converters, but only one player Temp Assured at current. Give me some time to research Parallax Power Supply Temperature Compensated Charging and roll some numbers using what little intelligence I have. I try to keep my Education and Intelligence separate, but it hurts...

[Beau388]

Originally Posted by dkoldman

I think I am breaking your rule on this thread. I am getting confused with my intelligence with education

I don't quite follow how you can get true battery readings without disconnection and I have never even heard of temperature being a factor for charging? If I am not edumacated real soon, I will have to call vMax Tank to see why they sold me those expensive AGM batteries knowing full well I had no method for temperature compensation?

It is the batteries that need the voltages of the converter controlled. Both Progressive Dynamics (Charge Wizard) and Parallex Power Supplies (Tempassure) offer power centers and refit converters with temperature compensation.
Price for the Tempassure module is about $75 for the wired version and $200 for the wireless.
My Parallex 5375 came with a wired Tempassure and 50 ft of data cable.

[dkoldman]

Originally Posted by Beau388

It is the batteries that need the voltages of the converter controlled. Both Progressive Dynamics (Charge Wizard) and Parallex Power Supplies (Tempassure) offer power centers and refit converters with temperature compensation.
Price for the Tempassure module is about $75 for the wired version and $200 for the wireless.
My Parallex 5375 came with a wired Tempassure and 50 ft of data cable.

After some review, I see this is not practical option for me. It would be cheaper to buy new AGM batteries when needed. It is still not clear how long the charging voltage being determined by temperature will extend the life of the battery? I saw somewhere by Tempassure it was 2 to 3 times longer? Is Tempassure saying batteries can go 20 years? I am not buying that... my AGMs who VMax says can last up to 8 - 10 years with my Progressive Dynamics Charge Wizard. The Progressive Dynamics Charge Wizard battery voltage and battery usage then selects one of the following four operating modes to properly charge and maintain the battery.
BOOST Mode 14.4 Volts – Rapidly brings the RV battery up to 90% of full charge.
NORMAL Mode 13.6 Volts – Safely completes the charge.
STORAGE Mode 13.2 Volts – Maintains charge with minimal gassing or water loss.
EQUALIZATION Mode 14.4 Volts – Every 21 hours for a period of 15 minutes prevents battery stratification & sulfation – the leading cause of battery failure.

The Tempassure and Power Centers do similar but use Temperature. I think Usage is big factor and I like the way mine detects when in storage and provides a boast every 21 hours to prevent stratification.

The reason why it is not practical for me is because my Converter is separated from my Breaker / Power Center. I am not gonna fool with that just to get some perceived advantage life on battery. There is no probe option for Progressive Dynamics; only if you buy a new Power Center and rewire

With that said, it is interesting technology, but don't see it as an absolute for extended battery life. I put it with Lithium batteries; both will likely be in my future but only when / if it comes installed as standard equipment from RV Mfg.

Here is my Progressive Dynamics 9200 Inteli-Power with 4 Stage Charge Wizard https://www.progressivedyn.com/rv/po...er-converters/

Thanks for sending me the info

[Logcabiny]

Originally Posted by dkoldman

Any reason you would not disconnect at both negative sides of each series?

I would prefer to disconnect both positive terminals and have to waving negative ends risking touching some grounded frame rather than the other way around. That is assuming the negative is grounded to frame at some point.

[Beau388]

Originally Posted by dkoldman

[snip]
The reason why it is not practical for me is because my Converter is separated from my Breaker / Power Center. I am not gonna fool with that just to get some perceived advantage life on battery. There is no probe option for Progressive Dynamics; only if you buy a new Power Center and rewire

With that said, it is interesting technology, but don't see it as an absolute for extended battery life. I put it with Lithium batteries; both will likely be in my future but only when / if it comes installed as standard equipment from RV Mfg.

Here is my Progressive Dynamics 9200 Inteli-Power with 4 Stage Charge Wizard https://www.progressivedyn.com/rv/po...er-converters/
Thanks for sending me the info

I agree modification are a personal choice. I was trying to show that cheap fixed voltage chargers can harm batteries in rare cases. The points you make a valid. For all antimony alloyed flooded batteries here are Trojan's recommendations. As a side note, I went out to exercise the generator this afternoon the ambient 98 F and the sun was shinning on the right side of the coach, The temperature of the two batteries in the compartment was 118 F.



4. How much should I compensate the charge voltage for temperature?

• Temperature will affect voltage readings. As temperature increases, voltage decreases. Conversely, as temperature decreases, voltage increases. Here are the relationships:
• Trojan recommends using the following: For every 1º F below 77º F add 0.0028 volts per cell or for every 1 C below 25º C add 0.005 volts per cell to the charger voltage setting.
• 1: A 12 volt battery @ 70º F. The recommended charging voltage at 77º F is 14.8 volts. The adjusted charging voltage is 14.8 + (6 cells * 7 degrees below * 0.0028) = 14.92 volts.
• 2: A 12 volt battery @ 21º C. The recommended charging voltage at 25º C is 14.8 volts. The adjusted charging voltage is 14.8 + (6 cells * 4 degrees below * 0.005) = 14.92 volts.
• For every 1º F above 77º F subtract 0.0028 volts per cell or for every 1º C above 25º C subtract 0.005 volts per cell to the charger voltage setting
• 1: A 12 volt battery @ 85º F. The recommended charger voltage at 77º F is 14.8 volts. The adjusted charging voltage is 14.8 – (6 cells * 8 degrees above * 0.0028) = 14.67 volts.
• 2: A 12 volt battery @ 29.5º C. The recommended charger voltage at 25º C is 14.8 volts. The adjusted charging voltage is 14.8 – (6 cells * 4.5 degrees above * 0.005) = 14.67 volts.
  • 5. Is there a maximum temperature for charging my batteries?

When charging lead acid batteries, the temperature should not exceed 120ºF. At this point the battery should be disconnected from all charging sources and loads in order to cool before resuming the charge process.

[dkoldman]

Originally Posted by Logcabiny

I would prefer to disconnect both positive terminals and have to waving negative ends risking touching some grounded frame rather than the other way around. That is assuming the negative is grounded to frame at some point.

I can see your logic with disconnecting both positives. I have a tendency to always disconnect negative posts 1st. I don't like sparks. Agreed that protecting the ends from touching a ground is a required step.

My question was trying to see if the poster had some special reason for disconnecting one positive and one negative? I am gonna assume not.

[dkoldman]

Originally Posted by Beau388

I agree modification are a personal choice. I was trying to show that cheap fixed voltage chargers can harm batteries in rare cases. The points you make a valid. For all antimony alloyed flooded batteries here are Trojan's recommendations. As a side note, I went out to exercise the generator this afternoon the ambient 98 F and the sun was shinning on the right side of the coach, The temperature of the two batteries in the compartment was 118 F.

4. How much should I compensate the charge voltage for temperature?

• Temperature will affect voltage readings. As temperature increases, voltage decreases. Conversely, as temperature decreases, voltage increases. Here are the relationships:
• Trojan recommends using the following: For every 1º F below 77º F add 0.0028 volts per cell or for every 1 C below 25º C add 0.005 volts per cell to the charger voltage setting.
• 1: A 12 volt battery @ 70º F. The recommended charging voltage at 77º F is 14.8 volts. The adjusted charging voltage is 14.8 + (6 cells * 7 degrees below * 0.0028) = 14.92 volts.
• 2: A 12 volt battery @ 21º C. The recommended charging voltage at 25º C is 14.8 volts. The adjusted charging voltage is 14.8 + (6 cells * 4 degrees below * 0.005) = 14.92 volts.
• For every 1º F above 77º F subtract 0.0028 volts per cell or for every 1º C above 25º C subtract 0.005 volts per cell to the charger voltage setting
• 1: A 12 volt battery @ 85º F. The recommended charger voltage at 77º F is 14.8 volts. The adjusted charging voltage is 14.8 – (6 cells * 8 degrees above * 0.0028) = 14.67 volts.
• 2: A 12 volt battery @ 29.5º C. The recommended charger voltage at 25º C is 14.8 volts. The adjusted charging voltage is 14.8 – (6 cells * 4.5 degrees above * 0.005) = 14.67 volts.
  • 5. Is there a maximum temperature for charging my batteries?

When charging lead acid batteries, the temperature should not exceed 120ºF. At this point the battery should be disconnected from all charging sources and loads in order to cool before resuming the charge process.

This is really some great stuff, as I have learned more; I see this has become another topic and I have created a new thread

https://www.thorforums.com/forums/f2...tml#post353105