Best battery for Scamp 13.

[Gompka]

its a progressive dynamics pd9130, they have pretty detailed specs on the pd website, not sure if they get "that" detailed though. Manual

[Gompka]

The charge wizard page has some charging curve graphs, they are voltage based, but you can more or less calculate the current. Wizard

[zack sc]

Originally Posted by Gompka

its a progressive dynamics pd9130, they have pretty detailed specs on the pd website, not sure if they get "that" detailed though. Manual

Thanks Gompka. Looks like the pd9130 has a maximum current of about 30 amps, so I am thinking that if I use about 30 amp-hours out of my 100 amp-hour deep-cycle Trojan 12 volt battery, I should be able to recover most of that charging on shore power within an hour or two. Am I understanding that correctly?

[Gompka]

Originally Posted by zack sc

Thanks Gompka. Looks like the pd9130 has a maximum current of about 30 amps, so I am thinking that if I use about 30 amp-hours out of my 100 amp-hour deep-cycle Trojan 12 volt battery, I should be able to recover most of that charging on shore power within an hour or two. Am I understanding that correctly?

Seems right to me, their graphs are based on a 155 amp hour battery and their 55 amp charger. They all are able to boost charge up to about 90% before a float so an hour or two seems to be reasonable. To get you back up to atleast 90%.

[zack sc]

Originally Posted by Gompka

Seems right to me, their graphs are based on a 155 amp hour battery and their 55 amp charger. They all are able to boost charge up to about 90% before a float so an hour or two seems to be reasonable. To get you back up to atleast 90%.

Thanks. So it seems like it would be pretty common to end up with a 12 volt battery spending a lot of time at about 90% charge. Is 90% high enough to not be bad for the longevity of the battery?

[Byron Kinnaman]

Originally Posted by zack sc

Does anyone know the specs for the onboard charger that Scamp sells with the Scamp 13? For a 12 v battery between about 50% and 80% charged, what charging current would the onboard charger supply?

PS. Or does that depend substantially on the internal resistance of the battery?
PPS. I know the last 20% or so is more complex. I am interested in the charging rate for the easy part.

My advice don't try to over think it.

[sokhapkin]

Originally Posted by zack sc

Thanks. So it seems like it would be pretty common to end up with a 12 volt battery spending a lot of time at about 90% charge. Is 90% high enough to not be bad for the longevity of the battery?

90% is fine. Try to not go lower than 50%.

[zack sc]

Originally Posted by sokhapkin

90% is fine. Try to not go lower than 50%.

yes, I definitely plan to stay above 50%. But does leaving in at 80% for a few days hurt it. I am asking because sometimes I could get to shore power, but it would be easier not to. How long can I leave in at around 60%, 70% or 80% without doing some harm?

[zack sc]

Originally Posted by Byron Kinnaman

My advice don't try to over think it.

Thanks Byron. I don't believe that I am overthinking it. Eventually I will learn it all empirically, but I would just like to understand and anticipate a bit and take good care of my new trojan battery that I am getting next week.

Modesty aside, I am actually pretty knowledgable about Li-ion batteries due to car and bike experience, but I don't know nearly as much about 12 volt battery characteristics and charging protocols, and so I am trying to get up to speed on that.

[zack sc]

Speaking of which, does anyone know roughly how fast my 2008 4Runner would tend to charge the deep-cycle trailer battery at around 70% SOC? I am guessing 20 to 40 amps, but I really have no idea. I would love to be able to anticipate how much charging I will get from driving and whether I need to go out of my way for shore power or not.

[Jon Vermilye]

I would be very surprised to see 20 amps, let alone 40 amps from a tow vehicle unless you have modified (ie increased wire size) the vehicle & maybe even the trailer. While the alternator may be capable of producing the current, the wiring is generally too small for more than 10 - 15 amps getting to the trailer battery.

[Jon Vermilye]

Originally Posted by zack sc

yes, I definitely plan to stay above 50%. But does leaving in at 80% for a few days hurt it. I am asking because sometimes I could get to shore power, but it would be easier not to. How long can I leave in at around 60%, 70% or 80% without doing some harm?

In one way I agree with Byron - If you purchase cheap batteries & replace them when needed, they will meet the needs of most.

On the other hand, if you want to get the most life from a lead acid battery, you must get them to a full charge as often as possible. One of the enemies of lead acid batteries is sulfation. To prevent this, you need to hit the battery hard enough to "beat" the sulfate deposits off the plates of the battery. This is best done by fully charging the battery, and periodically over voltaging it for short times (the equalization stage of a multi stage charger or converter).

Continually running between 50% & 80% without often going to 100% will definitely shorten the life of your battery, but this is what most do.

One of my favorite sites for battery information is Battery University.
Here is the page on Sulfation.

[John in Santa Cruz]

Originally Posted by zack sc

Thanks Gompka. Looks like the pd9130 has a maximum current of about 30 amps, so I am thinking that if I use about 30 amp-hours out of my 100 amp-hour deep-cycle Trojan 12 volt battery, I should be able to recover most of that charging on shore power within an hour or two. Am I understanding that correctly?

not quite. your power converter *can* output 30 amps, but it won't pump that much into the battery, thats the maximum total output including all possible loads in the camper. the amount of current sucked in by the battery will be a function of the voltage, and will probably be max 8-10 amps when the battery is quite far discharged, and less as the battery charge level rises. plus, there's loss in the system, amp*hours in is not the same as amp*hours out.

[zack sc]

Originally Posted by John in Santa Cruz

not quite. your power converter *can* output 30 amps, but it won't pump that much into the battery, thats the maximum total output including all possible loads in the camper. the amount of current sucked in by the battery will be a function of the voltage, and will probably be max 8-10 amps when the battery is quite far discharged, and less as the battery charge level rises. plus, there's loss in the system, amp*hours in is not the same as amp*hours out.

Thanks a lot John!

[zack sc]

Originally Posted by Jon Vermilye

In one way I agree with Byron - If you purchase cheap batteries & replace them when needed, they will meet the needs of most.

On the other hand, if you want to get the most life from a lead acid battery, you must get them to a full charge as often as possible. One of the enemies of lead acid batteries is sulfation. To prevent this, you need to hit the battery hard enough to "beat" the sulfate deposits off the plates of the battery. This is best done by fully charging the battery, and periodically over voltaging it for short times (the equalization stage of a multi stage charger or converter).

Continually running between 50% & 80% without often going to 100% will definitely shorten the life of your battery, but this is what most do.

One of my favorite sites for battery information is Battery University.
Here is the page on Sulfation.

That is great advice. Really helpful and really appreciated!!!
( sounds like a 12 volt LA is more difficult to manage properly than Li-ion, which is very happy between 25% and 80%)

But I will try to do all that and I think I can now that I know it is important.

[zack sc]

Originally Posted by Jon Vermilye

One of the enemies of lead acid batteries is sulfation. To prevent this, you need to hit the battery hard enough to "beat" the sulfate deposits off the plates of the battery. This is best done by fully charging the battery, and periodically over voltaging it for short times (the equalization stage of a multi stage charger or converter).

Continually running between 50% & 80% without often going to 100% will definitely shorten the life of your battery, but this is what most do.

One of my favorite sites for battery information is Battery University.
Here is the page on Sulfation.

Will the Progressive Dynamics PD9130 converter in my Scamp (2015) be able to do a proper absorption cycle charging on my new deep cycle battery? I read the manual, but it wan't really clear. Will it kick up the voltage to around 14.4 volts at the appropriate time if I leave it plugged in overnight?

[John in Santa Cruz]

Originally Posted by zack sc

Will the Progressive Dynamics PD9130 converter in my Scamp (2015) be able to do a proper absorption cycle charging on my new deep cycle battery? I read the manual, but it wan't really clear. Will it kick up the voltage to around 14.4 volts at the appropriate time if I leave it plugged in overnight?

The 4600 series are 4 stage smart chargers, I believe the 9130 is just a fixed 13.6v

[gordon2]

Originally Posted by John in Santa Cruz

..I believe the 9130 is just a fixed 13.6v

Quoting the P.D. website for the PD9130:

the built-in TCMS (Total Charge Management System) connector allows the RV manufacturer, dealer, or owner to easily add the Charge Wizard. The Charge Wizard is a microprocessor-controlled system that constantly monitors the battery voltage and use to ensure a rapid; yet, safe, recharge. The Charge Wizard can select one of three charging voltages and one of four operating modes depending on the condition and use of the battery.

So add the Charge Wizard (est $25) and you have a four stage charger that WILL run an EQUALIZATION Mode (14.4 Volts) every 21 hours.

(Note that the PD 9200 series of converters have the charge wizard circuit built in)

[zack sc]

Thanks Gordon and John. I ordered the charge wizard today. That seems perfect. Thanks Gordon for clarifying that for me!

Just for my own knowledge, would the PD9130 (without the charge wizard and thus with its voltage limited to 13.6 volts) will it eventually get a 105 amp deep cycle battery (Trojan TMX) charged all the way? If you were already at 80% and left it plugged in overnight, would it be able to power through what should be the absorption part of the charge cycle, or would the battery tend to stay stuck at around 80 or 90% charge?

Similarly, I am thinking that my tow vehicle (2012 4Runner) is not going to be able to get the charge of a deep cycle battery past about 85 or 90%, and I might develop sulfating issues if I relied on that. Does that seem correct?

[gordon2]

Originally Posted by zack sc

...would the PD9130 (without the charge wizard and thus with its voltage limited to 13.6 volts) will it eventually get a 105 amp deep cycle battery (Trojan TMX) charged all the way? ...

My understanding is that yes it will fully charge the battery.. and then keep charging it to such an extent that the water / acid will need to be topped off more often, and if you fail to do so, the battery will be "fried" or "boiled" eventually.
The fourth stage, at over 14 volts, is to desulfurize. which helps to extend battery life since sulfurization is one of the things that kill lead acid batteries. (see 12 volt side of life)

Originally Posted by zack sc

...Similarly, I am thinking that my tow vehicle (2012 4Runner) is not going to be able to get the charge of a deep cycle battery past about 85 or 90%, and I might develop sulfating issues if I relied on that. Does that seem correct?

Its very much dependant on the vehicle, the wiring, etc. I would consider a tow veh charge line to only be a supplement.. to restore a partial charge in between full charges from a good converter or other smart charger. Or to reduce the amount of discharge when running a fridge on DC.. the net discharge can still be positive or negative, but is less with a charge line.