My Sams Club / Duracell golf cart batteries ( made by East Penn) worked great for about 6 years.
I wouldn’t worry about the fact that they are from Costco.
I wouldn’t worry about the fact that they are from Costco.
The cheap batteries
- Thread starter john6206
- Start date
LFP batteries can not be charged below freezing.
I've never heard of not charging LA batteries below freezing. The AGM battery in my truck gets charged when it is running and below freezing.
I've never heard of not charging LA batteries below freezing. The AGM battery in my truck gets charged when it is running and below freezing.
If your batteries are disconnected and in your basement you probably won't even need to charge them again until spring when you bring them back to the boat. Your batteries will be fine (for what they are) for many years to come. I'm assuming that these 2 batteries make up your house bank (which you probably use for starting as well). You have 190 AH total capacity and only 95 AH useable capacity (by limiting discharge to 50% max). I'm confused by your statement that time spent sailing and on the hook "drains" it. What do you mean by that? Are you saying that a day sail drains the batteries down to 50%. What exactly do you mean? During a 24 hour period on anchor, your refrigerator can use up nearly all the capacity of your batteries (to 50%). Is that what you experience?
The surveyor probably made his comment based on his assumption that 2 grp 27 batteries for the house bank on a 32 foot boat used for cruising is probably woefully inadequate. He probably assumed that you would replace these batteries so that you would have the capacity more suitable for your use. I wouldn't come down so hard on the surveyor. He probably looked at 2 grp 27 batteries on a Catalina 320 and said "are you kidding?" That would be my reaction. The boat came standard with 2 4D sized batteries (for house bank) that should give you about 400 AH total capacity (200 AH useable).
If you have your boat on shore power, the batteries are virtually fully charged all the time and your batteries aren't suffering. The time you spend motoring is probably meaningless. You start out with fully charged batts so the alternator doesn't have to work at all. When you leave an anchorage after a full day and night on the hook, then you need to rely on your alternator but once you are started and going back to your slip, your batts will soon be fully charged again. If you aren't discharging your batts to 50% on every outing your batts are probably going to last far longer than you need them to last.
The surveyor probably made his comment based on his assumption that 2 grp 27 batteries for the house bank on a 32 foot boat used for cruising is probably woefully inadequate. He probably assumed that you would replace these batteries so that you would have the capacity more suitable for your use. I wouldn't come down so hard on the surveyor. He probably looked at 2 grp 27 batteries on a Catalina 320 and said "are you kidding?" That would be my reaction. The boat came standard with 2 4D sized batteries (for house bank) that should give you about 400 AH total capacity (200 AH useable).
If you have your boat on shore power, the batteries are virtually fully charged all the time and your batteries aren't suffering. The time you spend motoring is probably meaningless. You start out with fully charged batts so the alternator doesn't have to work at all. When you leave an anchorage after a full day and night on the hook, then you need to rely on your alternator but once you are started and going back to your slip, your batts will soon be fully charged again. If you aren't discharging your batts to 50% on every outing your batts are probably going to last far longer than you need them to last.
It looks to me like the previous owner needed to replace the batteries and since he was selling the boat, he went the cheapest route and provided 2 grp 27 batts just to get the boat sold. He probably took out his used 4D-sized batts when they were done. The surveyor probably recognized that this was a ridiculous maneuver and made his suggestion that you replace them with a suitable battery bank at your earliest opportunity. The grp 27's were simply a stop gap for the previous owner to sell the boat.
Lead acid can be charged below freezing without issue. The ideal charge voltage is inversely related to temperature, so charging them at low temperature without a temperature sensor might leave them just a little under charged, but still better than not charging at all. Lithium can be damaged by charging below freezing.
That’s pretty nice that the boat comes with 2x4D’s. Our Beneteau 37 came standard with two group 31’s, so I wouldn’t be surprised to see a 32’ boat with two group 27’s. With refrigeration, electronics, and various other loads we were generally good for up to 20 hours. We added a third group 31 a couple years ago just to have a little better margin for our needs. Before upgrading I’d recommend the OP consider what loads they expect to have and make an energy budget to see what might be the most worthwhile upgrade.
