how do you equalise your batteries?

GrahamM376 said:
Not for my T125s 2.58v/cell = 15.48v with 2 batteries in series.
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Quite correct according to Trojan's documentation for T105s. I haven't had to equalise my batteries yet and that's after about 2.5 years service. I live on board for around 6-7 months each year and am at anchor for a high proportion of the time. Batteries are left on charge over winter via 65W solar panel with a top up from shore power when required. I've just asked the yard to put boat on charge for a week as telemetry shows charge level around 93% (must have had a long run of cloudy days in Vigo).

I found that I had to adjust my Marlec HRDi regulator during summer as it was throwing useful solar power away well before the batteries were charged. Not a huge increase in voltage, just a slight tweak. However, it did prove to me that I could adjust the voltage up to 15.5V if equalisation was needed. I haven't tried it yet but would probably do it by charging in a marina for 2 days and then bumping the HRDi setting to 15.5V for the day. Summer setup has Rutland 913 and 145W solar charging via HRDi. It would be a pain as I'd need to isolate all devices on board for the day (so no cold beer).

My mains charger could probably be adjusted for an eq. charge by altering DIP switches and adjusting a pot. inside the case. However, tweaking the HRDi settings seems likely to work if I ever need it.

I decided not to buy any gear specifically for equalising as my T105s don't appear to require it very often (if ever). Maximum variation in SG was 0.025 but this fell back to 0.015 three weeks later. Variation of 0.015 SG after temp. correction seems normal for my T105s.

Trojan documentation: Trojan recommends equalizing only when batteries have low specific gravity, below 1.250 or wide ranging specific gravity, 0.030, after fully charging a battery. Gel or AGM batteries should never be equalized.
 
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Mistroma said:
Quite correct according to Trojan's documentation for T105s. I haven't had to equalise my batteries yet and that's after about 2.5 years service. I live on board for around 6-7 months each year and am at anchor for a high proportion of the time. Batteries are left on charge over winter via 65W solar panel with a top up from shore power when required. I've just asked the yard to put boat on charge for a week as telemetry shows charge level around 93% (must have had a long run of cloudy days in Vigo).

I found that I had to adjust my Marlec HRDi regulator during summer as it was throwing useful solar power away well before the batteries were charged. Not a huge increase in voltage, just a slight tweak. However, it did prove to me that I could adjust the voltage up to 15.5V if equalisation was needed. I haven't tried it yet but would probably do it by charging in a marina for 2 days and then bumping the HRDi setting to 15.5V for the day. Summer setup has Rutland 913 and 145W solar charging via HRDi. It would be a pain as I'd need to isolate all devices on board for the day (so no cold beer).

My mains charger could probably be adjusted for an eq. charge by altering DIP switches and adjusting a pot. inside the case. However, tweaking the HRDi settings seems likely to work if I ever need it.

I decided not to buy any gear specifically for equalising as my T105s don't appear to require it very often (if ever). Maximum variation in SG was 0.025 but this fell back to 0.015 three weeks later. Variation of 0.015 SG after temp. correction seems normal for my T105s.

Trojan documentation: Trojan recommends equalizing only when batteries have low specific gravity, below 1.250 or wide ranging specific gravity, 0.030, after fully charging a battery. Gel or AGM batteries should never be equalized.
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Interesting, ta. A few thoughts, I've always thought of equalising as preventive, if a problem shows it's maybe too late, also on a cruising boat seen it mainly as a way to stop sulfation and not so much for stratification. Problem being at anchor is getting the batteries properly back up to full charge which take a long time, I suspect few cruising boats regularly get their batteries up near 100%

Another problem is knowing when they are actually back near full, messing about with hydrometers isn't ideal, I usually assume if the voltage is up above14v and amps in is low single figures then they're pretty close to full, but that means no domestics running, thing I might fit another ammeter just measuring into the battery. How do you do it?

Very interesting ebook here, unfortunately you need to pay to get the whole thing......
http://www.morganscloud.com/2010/08/02/agm-battery-test-part-1/
Written with collaboration from lifeline. Who, interestingly for AGM batteries, actually recommend equalising.

But it's quite a vague area in some respects, I'm not completely convinced by trojans "only equalise if the SG of each cell varies", suspect that might not be ideal for a cruising boat batteries which may well not get a full charge every time.
 
I seem to remember reading a lot of stuff by Morgan's Cloud a few years ago. His web-site indicated that he seemed to spend a lot of effort equalising his Lifeline AGMs regularly. I remember details of disconnecting kit, removing covers, applying ventilation, lot of time monitoring temperature, current and voltage. He couldn't check SG as the batteries were sealed AGMs (seemed to be the only manufacturer suggesting eq. for AGM).

I've always assumed that eq. charging will increase shedding of material from plates and so best not to do it too often. I try to get the batteries back to 100% every 2-3 weeks and cycle 70%-85% in between. I actually managed to get back to 100% on Smartgauge this year as there were a lot of sunny and windy days. The gauge was sometimes at 100% by 11am mid-season. I imagine that's another reason that I haven't been tempted to do an eq. charge for the hell of it.
 
Mistroma said:
I seem to remember reading a lot of stuff by Morgan's Cloud a few years ago. His web-site indicated that he seemed to spend a lot of effort equalising his Lifeline AGMs regularly. I remember details of disconnecting kit, removing covers, applying ventilation, lot of time monitoring temperature, current and voltage. He couldn't check SG as the batteries were sealed AGMs (seemed to be the only manufacturer suggesting eq. for AGM).

I've always assumed that eq. charging will increase shedding of material from plates and so best not to do it too often. I try to get the batteries back to 100% every 2-3 weeks and cycle 70%-85% in between. I actually managed to get back to 100% on Smartgauge this year as there were a lot of sunny and windy days. The gauge was sometimes at 100% by 11am mid-season. I imagine that's another reason that I haven't been tempted to do an eq. charge for the hell of it.
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It does seem to be quite a big deal on Morgans cloud to equalise, but so far looks like it's paying off, latest batteries seem to be lasting very well according to their recent update. They get worked very hard as well, it's a power hungry boat.

So one question re equalising could be what's going to do the battery more harm, plate shedding or sulfation.

Where's the batt guru gods? There are a select one or two on here who really know the ins and outs of lead acid.
 
GHA said:
Problem being at anchor is getting the batteries properly back up to full charge which take a long time, I suspect few cruising boats regularly get their batteries up near 100% ....Another problem is knowing when they are actually back near full, messing about with hydrometers isn't ideal.
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In summer (away from the UK) I find solar keeps them topped up much better than the engine does as charge voltage is higher. I rely on the BM1s to give me a reasonable estimate of what's gone in/out.

Replaced one house bank with so-called "leisure" 110s 3 years ago, they're already knackered but the Enersol 130s on the other bank have lasted 6 years. Just binned the lot and installed Trojans.
 
Google came up with this which might be on interest, using resting voltage and a known amp/time partial discharge to try and get some handle on battery capacity, something difficult to do onboard. Perhaps not very accurate in actual Ahs but might be an achievable method of finding out if an equalise on aging batteries has helped or not.
What WILL be revealing, though, is to discharge the battery at the theoretical 20 hour rate for an hour (at least 1/2 hour), let the battery recover for at least an hour and measure the standing voltage and use a "look-up" table to determine approximate state-of-charge and using simple algebra calculate the capacity from that information
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http://www.cruisersforum.com/forums/f14/evaluating-12vdc-flooded-cell-batteries-12707.html

Thread 13 is also interesting regarding pulse equaliser devices, shame the graphs are no longer online but seems to be fairly well carried out testing....
You'll be interested to know that after almost six months of testing using the above methodology, we decided to equalize the T-105s ONE TIME to see what would happen. Presto...the results were much more positive than had been the pulsing/charging/discharging over the previous six months.
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Also, min the "discharge" page on the trojan site they do recommend equalising if the batteries aren't getting a full charge..

5. Many experts recommend operating batteries only between the 50% to 85% of full charge range. A periodic equalization charge is a must when using this practice.
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I think long distance boats don't get sulfation or need to equalize because the batteries are being charged all the time, in our case by a wind generator or by the generator or shore power, that was my experience.
 
I have an adjustable regulator I had to buy it as the marlec one I had got blown up by a lighting strike when I was anchored in South Carolina.So you would have to send off for it(westmarine FLEXCHARGE 25a) I've had that one about 12 years,it still works.
GHA said:
Why is that?

Thinking about it a bit more, there would be plenty of power on a breezy sunny day if somehow it could be controlled, why not an adjustable solar/wind regulator, if such a thing exists.

It would be nice to have some control over the voltage anyway, trojan recommend 14.8v, the regulators I've seen are fixed lower than that.
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rubbishman said:
I have an adjustable regulator I had to buy it as the marlec one I had got blown up by a lighting strike when I was anchored in South Carolina.So you would have to send off for it(westmarine FLEXCHARGE 25a) I've had that one about 12 years,it still works.
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Perfect, thank you. And can parallel up the wind gen with solar through one unit, ideal.
 
If you really want to DIY this, AND you have a charging device with a separate voltage sense wire, then just put a few diodes in the sense path until the voltage is what you want. Each one will probably increase the voltage by between 0.5V to 0.7V, less if you use Schottky diodes. Use a switch to bypass them when not needed.
 
nigelmercier said:
If you really want to DIY this, AND you have a charging device with a separate voltage sense wire, then just put a few diodes in the sense path until the voltage is what you want. Each one will probably increase the voltage by between 0.5V to 0.7V, less if you use Schottky diodes. Use a switch to bypass them when not needed.
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The flexcharge regulator sounds ideal for wind/solar, will be able to keep an eye on temperature adjustments as well,. And rf quiet which is a bonus. But think I should probably bite the bullet and replace an aging mains charger while we're at it, sterling pro charge ultra looks interesting.
 
GHA said:
Perfect, thank you. And can parallel up the wind gen with solar through one unit, ideal.
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I'm still quite happy with the Marlec HRDi regulator for combined solar and wind. I can see Amps/Watts to each battery (instantaneous or total over a number of hours). The menu allows me to alter the max. cell voltage over a wide range. I'll probably try it out at 15.48V sometime.

It is only a PWM regulator but might be worth considering if the Flexcharge option doesn't work out. A bit pricey if you don't have any need to monitor performance.
 
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Bit baffled by all this.
I expect the battery in my car to last 5 years at least. AFAIK the generator just gives 14point something volts into the battery; nothing about equalisation. How is the battery in my boat different?
 
Mistroma said:
I'm still quite happy with the Marlec HRDi regulator for combined solar and wind. I can see Amps/Watts to each battery (instantaneous or total over a number of hours). The menu allows me to alter the max. cell voltage over a wide range. I'll probably try it out at 15.48V sometime.

It is only a PWM regulator but might be worth considering if the Flexcharge option doesn't work out. A bit pricey if you don't have any need to monitor performance.
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Nice unit but budget advices otherwise :) Having had a dodgy solar panel trash 4 x us2200 batteries :(

Well, will be interesting to see if anything can be brought back by equalising, now they won't get the sg above about 1.200. Need something capable of equalising as well, looks like a new charger. But first a month abroad earning money to pay for it :)
 
blackbeard said:
Bit baffled by all this.
I expect the battery in my car to last 5 years at least. AFAIK the generator just gives 14point something volts into the battery; nothing about equalisation. How is the battery in my boat different?
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Car batteries have an easier life as they never really get away from being fully charged, unless sitting idle for a long time. Cruising boat batteries can have a much tougher time as often they won't get charged fully for a while, takes a long time to get the last bit of charge in there. They don't like that, have a look here..

http://support.rollsbattery.com/support/articles/5964-battery-sulfation
 
nigelmercier said:
Until you read all the negative comments on this forum. I researched this last year, best value and performance from CTEK.
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Had a quick look and any mentions of the ultra seemed to from happy customers.
https://www.google.co.uk/webhp?tab=ww#q=Site:www.ybw.com+pro+charge+ultra+
Plus had sterling kit on the boat for a long time with no problems, maybe I'm one of the lucky ones.
CTEK looks good on price but very low on configurability so no go there.
One shall carry on looking :)
 
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