Charger recommendations for C30

[Hayden Watson]

Any recommendations for a new charger for a C30.
I currently have one 4D lifeline with 210 ah. when I replace that I would like to double that capacity so I am thinking about going back to group 27 with a pair in the battery compartment and a second pair on the port side behind the holding tank.
How much charging should I have for 200 to 400 ah. What brand / model is best. I would really like to go the LiFePo4 in the next round of battery if they get the bugs worked out.

 

[LeslieTroyer]

I’d recommend Sterling in 60 or 40A versions from @Maine Sail. They won’t do lithum but not much will and if the do the typically don’t do fla, AGM.....

 

[jssailem]

Looking for 200-400 Amp Hours. Willing to spend about $600 for 4 batteries. Consider the Dyno Batteries from Seattle. The
30TMX was selling for about $150 each. They are a true deep cycle 12 V battery rated at 135amphr, 800 cycles, thick plates and only 65 lbs so not a back breaker to install. 4 of these would give you a total of 540 amphrs. All 12 volt.

Like @LeslieTroyer's recommendation of the Sterling 40amp charger from @mainesail

 

[dlochner]

The rule of thumb for battery chargers is 10% of the amp hour capacity, plus a little extra to run house loads while charging. Thus, the minimum for a 400 ah bank would be a 50 amp charger, 60 amp gives a little more wiggle room. When I replaced the charger on my boat with a 460 ah bank, I went with a 50 amp Pronautic P (same as a Sterling). There was a significant price increase to go to a 60 amp. After 4 seasons, I'm happy with it.

 

[Stu Jackson]

Hayden,

It all depends on how you use your boat. If you're a marina queen [and most likely YOU aren't], then a smaller charger would be just fine.
If you are away from docks often, and especially if you use a generator to power up your charger, your run time can be substantially reduced with a larger charger.
The identical Sterling or ProNautic chargers are among the best standalone units.

It would be good to replace your 4D, 'cuz it is not true deep cycle. TMX, DSCX at 12V or golf carts would do you well.

 

[Mikem]

As far as batteries go I'm with Jssailem and Dyno batteries. My first set of Dyno golf carts were still decent after 9 years. Also, Dyno batteries were the go to batteries when we were building escort tugs and pilot vessels at Marco Shipyard. Dyno makes only batteries and they are top notch. As far as a charger goes do what Maine sail says.

 

[Hayden Watson]

Hayden,

It all depends on how you use your boat. If you're a marina queen and most likely YOU aren't, then a smaller charger would be just fine.
If you are away from docks often, and especially if you use a generator to power up your charger, your run time can be substantially reduced with a larger charger.
The identical Sterling or ProNautic chargers are among the best standalone units.

It would be good to replace your 4D, 'cuz it is not true deep cycle. TMX, DSCX at 12V or golf carts would do you well.

Thanks for the complement Stu! No marina queens here. I am self-employed so when I am out on my boat, work goes with me so I need to use my inverter to power / recharge my computers. Minimizing the generator run-time is the goal. As for our 4D it is a Lifeline AGM and it deep-cycle rated. When cruising we discharge to about 20%SOC before recharging. I know that breaks the 50% rule but Lifeline says that it can handle it with minimal reduction in life. The battery is 6-7 years old and still going strong.

 

[Mark Maulden]

How do you know it’s still going strong? Basically, the only way to know is to perform a load test. So far, I cannot see the justification spending double for Lifelines over a good FLA. My Dyno GCs are 8 yrs old and “seemingly” still going strong. I do take care of them and they do experience PSOCs. Lifeline states their batts can be installed on their sides but caveat that by saying electrolyte can be expelled through the vent during a charging cycle and recommending a drip pan...Huh? My sterling charger has been working fine.

 

[Hayden Watson]

I got the Lifelines because they have low internal resistance which allows them to stay in bulk phase longer before dropping to absorption than is possible with FLA. The PO installed a 108-amp alternator but with 2 new Group 27 FLA’s I would only stay in bulk for a few minutes so most of the time my charging current was 50amps or less. With the Lifeline, I can stay in Bulk at 70+ amps for at least a half hour and even in absorption phase it will still take more than 50 amps. This greatly reduced the time it took to replace each day’s usage.

As for it still going strong, I do not have the gear to a capacity test. What I did do this summer was as follows. (MaineSail, please do not read the following because I know that it is blasphemy.)

I have a Link-10 and the first day of our cruise, I did not recharge until I got to -140 AH. Given that the 4D has a rated capacity of 210 that would be 33%-SOC. My resting voltage was in the mid 11.7 range. Which per the charts would be 10% to 20% SOC for OCV. My resting voltage was not really OCV because I was still using the battery the whole time for minor house loads including refrigeration so the true OCV and SOC would likely be higher. I did note that when recharging, I did not get as much time at bulk and after 1.5 hours I was only getting 45amps in absorption but that is still better than I would get from FLA so it is good enough for me. According to Lifeline, at a DOC of 80% the predicted Life cycles is in excess of 500. I go on several 1-2 week cruises per year and abuse it during the cruise but it is fully recharged at lease once during the cruise at our marina stop over and fully recharges when we get back to our dock so I am okay with that. I did the risk/reward cost analysis and for me the Lifeline has been a great choice. YMMV

I have been talking to other C30 Mk2 owners about where they located two additional house batteries and if I expand the bank, I might go back to FLA’s until LiFePo4 becomes a real possibility because doubling the bank size would allow me to use more of my charging capacity.

 

[Gunni]

With an AGM, you can go WAY up on charge output (because the battery will take it). You want a smart charger with battery temp sensing. You also want a external charge controller on your alternator that has temp sensing. As I read your battery charge test it seems that something is not right - your Lifeline should have stayed in bulk much longer.

I would not chase the hypothetical lithium future. Make your current system a fully integrated system. When lithium marine is ready for prime time you can decide if it is worth the effort.