BATTERED BY BATTERIES
Getting to the bottom of persistent power problems
Having completed an Atlantic crossing just two years earlier, Favorita, an old Bavaria 51, was kitted out to the blue-water specifications of the day, when I bought her back in 2003. Her power arrangements included a large bank of Trojan wet cell batteries. These were heavy, high maintenance, and made me nervous when heeled. They were charged by the standard engine alternator and a Victron shore charger/ inverter that could also be driven by the on-board 230V AC generator.
I added an arch with solar panels and a high-capacity alternator with a ‘smart’ regulator. I removed the generator, as I needed the space. I took the boat to Sweden and had to winterise her outside. I put a temperature switch on the shore charger set to switch on at zero. At some point my power lead was disconnected and the batteries froze. I returned to a bilge full of acid. The temperature had fallen to -25ºc.
I had four 110Ah Victron Absorbent Glass Mat (AGM) batteries installed – lighter, sealed and low maintenance.
GETTING ARC READY
We returned to a pile berth on the Hamble. The solar system was keeping the batteries topped up and I added an EFOY methanol fuel cell. Ten years after installation the Victrons were struggling to hold and deliver their amp hours. I was amazed at their longevity. I nursed them for another two years as I had Atlantic Rally for Cruiser (ARC) plans and wanted to delay replacement until nearer departure.
I researched replacements, assisted greatly by Barden UK, and settled on a bank of three 210Ah Rolls AGMS. These were big and heavy to install, but they made the best use of the battery space and brought my house bank up to 630Ah. Barden even loaned me an empty display model to ensure they would fit.
I installed them in March 2019, to allow testing time before the ARC. By now I had a broad set of charging solutions. A high output alternator on a smart regulator, a Sailgen towing generator, the fuel cell, a new Victron shore charger – to accept both USA and European supply – and the solar panels. The long life of the Victron bank was testament to the set up, and in late 2019 I fitted a new battery monitor to keep an eye on everything. We were ARC ready.
In July 2020 we headed south, sailing directly to Spain. Everything seemed fine in the electrical department, and we anchored our way through the beautiful Rias of Galicia, occasionally stopping in a marina to top up. I tried to get the battery to run down to about 60% of charge, thinking that batteries liked
to be worked. The batteries were hungry for current whenever I started the engine or plugged in ashore. I noticed that the voltage was dropping quickly when we disconnected. Voltage alarms sounded when the battery was only 10% down.
BATTERY FAILURE
As we sailed down the Portuguese coast I adjusted the alarm settings but found that we needed to stop at marinas to recharge even when we had only motored for part of the day. We could only just get through a night before lights dimmed and pumps slowed. Something wasn’t right.
I contacted Barden UK and they put me right on ‘voltage’ sensing – under load – and told me to use the state of charge percentage as my guide. I did this but was still struggling to get any reasonable Amp hours out. The whole bank was only able to deliver about 30Ah before the voltage dropped. The fridge compressor was struggling, and the EFOY fuel cell refused to charge the battery. My beautiful ‘new’ batteries were failing after 15 months. I was angry and confused.
With the impact and restrictions imposed by COVID-19, we decided to put a hold on our Atlantic adventure. We limped slowly down Portugal, loving the place, the people and the food. We arranged to winter in Portimao in the Algarve. On arrival I separated the individual batteries and tested them to see if there was a dud. The performance of each battery was essentially the same and my conclusion was that they needed replacement. I contacted Barden with my findings and started the Rolls warranty process.
THE WARRANTY PROCESS
I had to complete a form indicating the charging regime that the batteries had been subjected to. I had the manuals for the shore charger and the alternator smart charger – which had been the
My beautiful ‘new’ batteries were failing after 15 months. I was angry and confused
main chargers for the batteries. I had no information on the solar regulator, other than ‘dip switch’ settings set to ‘sealed’. I used the information from the manuals on the form, after all the batteries were AGMS and the previous AGMS had lasted so well. The Victron shore charger manual suggested that 14.4V was the normal setting for AGMS, the alternator regulator manual agreed.
My warranty claim was immediately rejected. I was told I had under-charged the batteries, which had most likely led to their sulphation and subsequent poor performance.
AGM REVELATION
All AGMS are not the same. I was told that Victron AGMS would be fine with a maximum voltage of 14.4V – the normal setting for ‘sealed’ on charger brands.
The Rolls batteries needed 14.8V for the main part of their charging cycle. This information was apparently clearly stated on a label on the side of the battery. I had assumed that AGM was AGM. I felt battered by batteries and suggested that placing this important label on the side of a battery made it difficult to see once they were in place.
I suggested that battery sales agents could draw attention to such key data, as not all purchasers in the marine sector are specialists – Barden had taken my old Victrons in part exchange. The sales team could also ensure that the charging regime was communicated in the supporting paperwork or invoice. I was angry at my own stupidity, but I was also indignant that this key information seemed so hard to find.
I crawled through all my manuals and set up my shore charger and the alternator regulator to the correct settings. This was not straightforward as you needed at least three hands. I could readily revise the settings from the EFOY fuel cell, but I had no way of checking the towing generator or the solar charger. I cycled the batteries hard but got no improvement in their condition. I needed new batteries.
I reported back to Barden and via them to Rolls. I was preparing to roll up my sleeves for a battle. My arguments concerned communication and labelling. Who knew 0.4V was of such importance?
MOVING FORWARD
Both Barden and Rolls had been efficient, considerate, and clear when faced with my panic. They continued in this line, explaining that the only way they could be sure of their interpretation was to test the batteries involved – now in Portugal. They offered a very fair deal for replacements and suggested that there might be some value in the ‘old’ ones if they could get an ‘equalisation’ charge.
They followed through with the deal, and I installed my ‘new’ batteries, carefully numbering them all to avoid confusion. I re-checked that the charging regime from all sources was compliant with the Rolls requirements. I am looking for a controllable maximum power point tracker (MPPT) charger for the solar and think I will manage the towing generator through the battery monitor, and simply lift it when needed.
This was an expensive lesson. Today’s cruising yachts are dependent on their batteries, and it surprised me how much I had still to learn.