Hi everybody, has anybody changed their lead acid batteries to lithium ion batteries on a 26m.
If so, a few questions I would like to ask or any recommendations you would kindly add.
1. What advantages do you get and is it worth the cost.
2. Is it difficult.
3. Would you do it again or is it not worth the bother.
4. What batteries and essential equipment would you recommend.
Thank you in advance if you reply.
Hi Brian, i converted my X house battery to lithium &found it straight forward transition. The lithium battery I use is overall half the size & weight of the 200ah lead acid battery I originally had. The only difference is that you will need to check to see if your chargers are compatible with the type of lithium you purchase. When looking for a lithium battery I would highly recommend one with a (BMS), battery management system , & with a heater. I can highly recommend this company for batteries. If by chance that you get one without a BMS then you will need to purchase a separate BMS. Also if your battery has no onboard heater you will need to keep the battery from cooling to below freezing.
https://sterling-power.com/
Hi Andrew, It is mainly the size and to a lesser degree the weight. I have two lead acid now which work ok for my needs on the lake but I dont like the way they are so tight in the compartment. One needs replacing this coming season and I was thinking of going lithium and doing away with the lead acid altogether. Do you still go on the lake and if so maybe we could meet up and have a chat when I go back in in April. Thanks for replying.
It's not something I've done, but in general, Lithium batteries perform better than lead-acid. However, the main issue is charging.
Your outboard is designed to charge a lead-acid starter battery, so you can't really swap that. But you should be able to replace a dedicated house battery (or bank of) with lithium, and to do that you will need a 12V to 12V lithium charger. The input is connected to the starter battery, thus getting power from the outboard, and the output goes to the lithium battery. You would need a switch arrangement to disconnect the charger from the starter when the engine is not running (could be automated). You must not connect a lithium battery directly to a lead-acid, even if they are both nominally 12V.
You would also need a mains charger for lithium if you want to charge the house battery from shore power. If you want shore power to be able to top up the starter battery, that would be a separate charger.
So you end up with the engine and house systems being completely separate. The old-style selector switch for picking which battery you're going to run from is a no-no!
Incidentally, outboards should not be connected to the starter battery via a switch anyway, because the alternators are not designed to run with no load and can be damaged. The starter battery should be permanently connected using those big thick leads that they arrive with.
Beyond that, I can't offer any recommendations or prices for specific equipment, hopefully someone with actual experience can chime in.
Rick Jones (Treasurer), former 26X & 19 owner, Isle of Wight
Hi Rick, I will check everything before I put it back in the water and decide. There is a lot to think about and not being technically minded I don't want to overpower the old brain and do it wrong. Thank you for taking the time to reply.
When I replaced my house battery I decided to stick with AGM for simplicity but I did buy a 12v to 12 charger to automatically connect them . I have a Renogy charger which also integrates my solar panel. The alternator connects to the starter battery as Rick says . I also have a AC to DC charger wired to my starter batter for shore power connection. That way the first point of charge either way is starter battery and it spills into the house assuming starter is full.
The Renogy permits remote switching of battery type so in theory I could also connect a Lithium battery to a selector
switch and then change it using phone app. The solar mainly charges the house battery but unlike Victron the Renogy can reverse trickle charge the starter battery as well.
I've replaced both starter and house batteries with LiFePO ones. Researched the matter first as a lot of controversy. The main problem is that while charging the LiFePO from alternator - battery takes all the current until full and BMS shuts, creating a spike in the system. This can damage both alternator and electronics. I have installed my system as follows: alternator charges NOCO NLP30 LiFePO starter battery first. Victron smart DC-DC charger is preset to start diverting current to the House LiFePO battery a couple of mV before the full voltage reached. Victron AC smart battery charger and Victron smart solar connected first to starter battery for the same reason. House battery is 200Ah and has permanent small electric drainage (handheld radio charger, portable WiFi, USB sockets ets, so never reaches its full BMS cut-off voltage. This system worked flawlessly for a couple of years for me. Waiting to hear from Jim (Harmony's new owner) to hear how it goes this season.
the only small negative feature is that NOCO NLP30 is a motorcycle style battery, very small capacity but with very high CCA output. It starts Yamaha 50 with ease, and re-charges virtually within a couple of minutes. Solar panel keeps it topped up in season absolutely fine. In winter I found solar to be insufficient however and this needs topping up from AC charger before the first use.
happy to give more details if needed.
best regards
Vlad
ex-Harmony
Hi Vlad, the last battery I changed was on my old Ford Cortina. It is certainly a lot more complicated these days ;-)
Thanks for chipping in.
When I replaced my house battery I decided to stick with AGM for simplicity but I did buy a 12v to 12 charger to automatically connect them . I have a Renogy charger which also integrates my solar panel. The alternator connects to the starter battery as Rick says . I also have a AC to DC charger wired to my starter batter for shore power connection. That way the first point of charge either way is starter battery and it spills into the house assuming starter is full.
The Renogy permits remote switching of battery type so in theory I could also connect a Lithium battery to a selector
switch and then change it using phone app. The solar mainly charges the house battery but unlike Victron the Renogy can reverse trickle charge the starter battery as well.
In addition , last summer I developed a novel, slightly back handed way if topping up my lithium trolling motor battery from the alternator. I made a high amperage DC cig lighter socket close to my switchboard and then plugged in my DC to AC inverter which is capapable of working my mains lithium battery charger which delivers 5 amps.......its back and forth and no doubt inefficient , but it worked !
Hi Roly, I went to bed last night, after reading the replies from Andrew and Rick, thinking blimey. I woke up to read the replies from you and Vlad and wonder is there any improvement that is simple and straightforward on a Mac. I'm not going to bother now asking for recommendations on what to use to clean and polish Mary Elizabeth ;-)
Thanks for your input and good sailing ths season.