1Louder
Explorer
So much to read and learn! Here's a very good site with info. http://outbackjoe.com/macho-diverti...ms-dual-batteries-solar-panels-and-inverters/
Dual Battery Shore Power Charging Question
- Thread starter 1Louder
- Start date
So much to read and learn! Here's a very good site with info. http://outbackjoe.com/macho-diverti...ms-dual-batteries-solar-panels-and-inverters/
DiploStrat
Expedition Leader
I like that site and agree with almost everything. If you look at my site, you will find most of the same information, only he goes MUCH deeper into the vagaries of B2B's etc. Going to have to add a link to my site. Do note that he is looking at Australian vehicles and products. The Blue Sea ACR, and, as far as I have seen, all other VSR's sold in the US, are all dual sensing, so you don't need to use two of them. (This addresses the issue you raised in your very first post. Remember that one?)
In any case, thank you for a link to a great site.
Other than the problem of charging an Odyssey battery as your starter battery on a Toyota, for smaller systems, the combination of the CTEK D250S combined with a SmartPass is pretty slick. Intelligent combination, decent charging profile for the second battery, close to full output from the alternator, and a 20A solar controller. Just be aware of the limits:
-- 100A or so max alternator output, and,
-- Only 20A of solar.
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Ducky's Dad
Explorer
Not trying to beat a dead horse here, but I have some new info. Since I'm thinking about getting another charger for my 2150, I refreshed my memory on the Odyssey charger recommendations (http://www.odysseybattery.com/documents/ODYSSEY_approved_12V_chargers.pdf ) and on the Ctek charger specs. Ctek just told me that the Odyssey charger chart linked here is just plain wrong. The Ctek MUS 25000 (25amp) does NOT have a "snowflake mode" for AGMs, and it has a peak charging voltage of 14.4V, rather than the 14.7V that Odyssey says their 2150 needs. Ctek told me to use the MUS 7002 (7amp) in snowflake mode (because it does deliver 14.7V) for charging the 2150, and they told me that the snowflake mode performs desulfation as part of its normal charge profile. Ctek said that the ah ratings listed on the Odyssey chart are grossly understated and that the 7002 is fine for batteries in the 100ah range and the 25000 is good for batteries up to 500ah. Ctek also told me that I should not recondition my 2150 more than about once per year because the reconditioning mode inputs up to 16.0V and carries some risk to electronics. Ctek told me that it is not necessary to disconnect the battery from load for normal charging/desulfating cycles, but probably a good idea to disconnect for reconditioning cycles. Ctek tech will contact Odyssey to get clarification on the charger recommendations. I also have a call in to Odyssey tech support to try to get this sorted out.
1Louder
Explorer
Great info. The price point on that is certainly more friendly. I went ahead and ordered one. I will report what I find in comparison to my Noco 3500.
Thanks for the update.
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Ducky's Dad
Explorer
More news! Odyssey and Ctek disagree about which chargers are appropriate for which batteries!!!!
I just got off the phone with Odyssey. Kathy in tech support told me that the Ctek 25000 is not "ideal" for the 2150/PM1, but that it will work better than the 7002, and that is why it's on their approved list. The 25000 has a charging voltage of 14.4V, below the 14.7 that is recommended, but it will fully charge a 2150 that is in good condition. However it will not fully desulfate a 2150, according to Kathy, because its amperage is too low. In my situation, she said that my truck's 270 amp alternator at cruising speeds will be putting out enough amps to desulfate the battery, and I can use the 7002 to top off or maintain the 2150 between trips. If I do ever need to recondition the battery, I can zap it with my 40-amp Ultimizer. Their charger recommendation for ideal rates is 40% of the battery's ah capacity, so that is a little more than 40 amps recommended for a 2150. They prefer 50 amps for that battery, but the 25 amps from the Ctek 25000 is at the bottom of the acceptable range. Some of their new Odyssey chargers will be available next month, but those will only be for the smaller batteries. The new 50-amp charger will not be available until spring, and they will no longer offer multi-bank chargers, just singles. She confirmed that the old Ultimizers were built for Odyssey by Schumacher, and the new line is being built by ProMarine in the USA, but they may use another vendor for the 50-amp units (can't talk about it now, etc.). If I get any more info, I'll post it here. What a PITA.
I just got off the phone with Odyssey. Kathy in tech support told me that the Ctek 25000 is not "ideal" for the 2150/PM1, but that it will work better than the 7002, and that is why it's on their approved list. The 25000 has a charging voltage of 14.4V, below the 14.7 that is recommended, but it will fully charge a 2150 that is in good condition. However it will not fully desulfate a 2150, according to Kathy, because its amperage is too low. In my situation, she said that my truck's 270 amp alternator at cruising speeds will be putting out enough amps to desulfate the battery, and I can use the 7002 to top off or maintain the 2150 between trips. If I do ever need to recondition the battery, I can zap it with my 40-amp Ultimizer. Their charger recommendation for ideal rates is 40% of the battery's ah capacity, so that is a little more than 40 amps recommended for a 2150. They prefer 50 amps for that battery, but the 25 amps from the Ctek 25000 is at the bottom of the acceptable range. Some of their new Odyssey chargers will be available next month, but those will only be for the smaller batteries. The new 50-amp charger will not be available until spring, and they will no longer offer multi-bank chargers, just singles. She confirmed that the old Ultimizers were built for Odyssey by Schumacher, and the new line is being built by ProMarine in the USA, but they may use another vendor for the 50-amp units (can't talk about it now, etc.). If I get any more info, I'll post it here. What a PITA.
DiploStrat
Expedition Leader
Conventional Wisdom
Conventional wisdom has always been to go with the battery manufacturer's recommendation over that of a battery charger.
Random musings: Is it worth the PITA to use an Odyssey battery? We are talking about the starter battery here, only 100Ah. Any reasonable alternator should be able to keep that healthy. Typically, the problem comes when trying to maintain a 400+ Ah battery bank. At that point getting even a minimal amp rate of 20A per 100Ah gets much harder. Sounds like there is a good argument to be made for not using Odyssey batteries as deep cycle camper batteries. My Lifeline AGM's can take a charge rate of up to 5/C (in my case, about 3000A) but they only need about 14.2-14.4v at 20C.
It would seem that the Odyssey might offer advantages in a smaller vehicle (e.g. Jeep, FJ) where you might use a pair of them for north starting and camping and dispense with any sort of isolator. But if the FJ can't keep one happy, how will it ever deal with two? Of course, a month jolt from a shore charger might help.
Conventional wisdom has always been to go with the battery manufacturer's recommendation over that of a battery charger.
Random musings: Is it worth the PITA to use an Odyssey battery? We are talking about the starter battery here, only 100Ah. Any reasonable alternator should be able to keep that healthy. Typically, the problem comes when trying to maintain a 400+ Ah battery bank. At that point getting even a minimal amp rate of 20A per 100Ah gets much harder. Sounds like there is a good argument to be made for not using Odyssey batteries as deep cycle camper batteries. My Lifeline AGM's can take a charge rate of up to 5/C (in my case, about 3000A) but they only need about 14.2-14.4v at 20C.
It would seem that the Odyssey might offer advantages in a smaller vehicle (e.g. Jeep, FJ) where you might use a pair of them for north starting and camping and dispense with any sort of isolator. But if the FJ can't keep one happy, how will it ever deal with two? Of course, a month jolt from a shore charger might help.
Ducky's Dad
Explorer
Obviously not for everyone. That is why, when I recently bought a 31M for my Tundra, I went with a Northstar. Same physical size as the Odyssey, same CCA, slightly better reserve capacity (220 mins vs 205mins), same price range. Northstar rep (obviously biased) told me that the Northstar does not have the same high voltage/high amp charging requirements as the Odyssey and that it should be a lot easier to maintain. I don't know if he is pulling my leg, but I'm going to find out. He also said that the Odyssey Ultimizer 40 amp charger will not damage the Northstar battery, but that it does not need that kind of charger. Optima told me to absolutely not use that charger on any of their batteries because damage would ensue. The Optima 31M has much lower capacity than the Odyssey or Northstar, and the Deka 31M was not readily available when I needed one.
Once I finish the current battery musical chairs, I will have one vehicle running a combination of Odyssey 2150 and Optima Blues, one running a single Northstar, one running dual Optima Yellows, and two running single smaller (G34) Odysseys. Pretty decent sample set. The only one that sees shore power charging is the Odyssey 2150, but I may just put them all on a top-off rotation with the Ctek 7002.
1Louder
Explorer
My battery was already on the Noco charger for 24 hours when I switched it to the new Ctek 7002 charger. The charger didn't detect any sulfation and just did a couple of hours of additional charging until it went into maintenance mode. Not a really fair test for the Ctek. It did at least show 14.7 volt charge which is much higher than the Noco ever did. The Noco specs says it can go to 14.7 but I never saw that during my random tests. Tonight I will take it off of the charger and check the voltage after an hour or so and then again in the morning. Hopefully there isn't a large drop.
I will need to re-install the PM-1 into my FJ and see how it does next week. Maybe then if the voltages drop again I can then hook it up to the Ctek to see if it will run through it's complete cycle. If/when all this gets working and if/when I decide to install a dual battery system back in my FJ I will leave all of my accessories hooked up to the more powerful PM-1 and then use the Yellowtop as just a backup.
I will need to re-install the PM-1 into my FJ and see how it does next week. Maybe then if the voltages drop again I can then hook it up to the Ctek to see if it will run through it's complete cycle. If/when all this gets working and if/when I decide to install a dual battery system back in my FJ I will leave all of my accessories hooked up to the more powerful PM-1 and then use the Yellowtop as just a backup.
Ducky's Dad
Explorer
That's pretty much the way my Dodge is set up. Everything runs off the 2150 starting battery, except for the refrigerator connected directly to the Optima Blues. But, my isolators and switches are set up so that I can add one or both of the Optimas into the system whenever I choose (nothing automatic), for winching, OBA, emergency starting, etc.
1Louder
Explorer
When I woke up in the morning the PM-1 dropped to 12.7 volts but has been holding that for a few hours. I need to see if I should try a recovery mode on it with the CTEK since the Odyssey wants to be at 13.1 when fully charged. At least it is out of my vehicle and easy to mess with. The Optima seems to be holding around 12.7. I just put my fridge in. ARB set at 38 degrees and it will be real hot today so I will see what the voltage shows after 4-5 hours.
Ducky's Dad
Explorer
Odyssey tech sheet says it wants to be above 12.84V at 100% charge.
http://www.odysseybattery.com/documents/US-ODY-OM-012_1014.pdf
If that is after a fresh charging cycle, it should be higher.
from Optima tech specs for G34 Yellow
https://d26maze4pb6to3.cloudfront.net/optimabatteries/4713/4583/5068/YELLOWTOP_Full_Specs_Sheet.pdf
1Louder
Explorer
Thanks, too many numbers. I had them backwards. More work needs to be done..... Good news I guess is the PM-1 has not dropped below 12.7 volts all day. So while it is not at 100% it's higher than it was. Ctek recovery mode is for deeply discharged batteries which it is not.
Edit: This morning the PM-1 is still holding steady at 12.7-12-71. I have the Optima back on the CTEK charger. In maintenance mode it is still showing 13.68 volts. Maybe that will help kick the Optima back up to 13.1. It will come off the charger in about 3.5 hours.
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C-Fish
Adventurer
1Louder
Explorer
Quick update: I left the PM-1 on the CTEK charger for a few days and it was holding at 12.9 volts (at least for a couple of hours.) I have re-installed it into the FJ along with the Fuse modification. We will see what happens. The fuse modification has bumped the alternator output to 14.0-14.1+ volts from a peak of around 13.9 (typically around 15.while at highway speeds.
I will follow up in a couple of days. Leaving the battery on the CTEK charger for several days while in maintenance mode seemed to bump the voltage up vs my less powerful Noco 3500. Still debating on the dual battery re-install. I have plenty of time to make that decision and can leave the Optima Yellow Top on charge with the CTEK for the time being.
Thanks everyone for all of the assistance. C-Fish also installed the same fuse mod and it about to take a longer trip. So we will see what his alternator does.
- Chris
I will follow up in a couple of days. Leaving the battery on the CTEK charger for several days while in maintenance mode seemed to bump the voltage up vs my less powerful Noco 3500. Still debating on the dual battery re-install. I have plenty of time to make that decision and can leave the Optima Yellow Top on charge with the CTEK for the time being.
Thanks everyone for all of the assistance. C-Fish also installed the same fuse mod and it about to take a longer trip. So we will see what his alternator does.
- Chris
Ducky's Dad
Explorer
Remember that you should measure OCV on the PM1 after the battery rests for at least 8 hours after coming off the charger. Need to let the surface charge dissipate. Or, you can flash off the surface charge by turning on the headlights for 30 seconds. Fun with batteries!