I spoke with Yamaha at length about lithium batteries, the big problem they had with them was their outboards and their variable magnetic field generator / alternators which are similar to an automotive generator.
Yamaha is pretty tight lipped about the charging output from the 1.8L & TR-1 1.049L engines. For the TR-1 engines, from what have read in the past is 14A per engine which is roughly 200 Watts from the PMG ( permanent magnetic generator) type alternator. Keep in mind this is the total output and an appreciable amount goes to operating each engine. This type of system is always at full output (excess output is shunted to ground) since the magnetic field is fixed which lends itself to use with LiFePO4 batteries. If Yamaha is not even testing them they are falling behind the curve. I’m planning on installing another smart shunt on the house battery in the next couple of weeks so I should have a better idea how much charging power actually goes into the house battery.
I had quite the journey when I went to LiFePO4 batteries which you can read about here:
Lots of great input from fellow members in that thread !
Summary:
I contacted several LiFePO4 battery manufacturers and the only two that I could actually talk to were ReLion and Battle Born. Dakota lithium would talk to you if it was sales, but for tech support it was only via email and would take up to 48 hours to get a response. I also felt like Dakota lithium is, well, lying about where they are located and infer their batteries are made. Dakota lithium talks about themselves being located in Grand Rapids North Dakota, but I could never locate them there, the only location I could find for them was in Seattle WA. But a lot of folks are happy with them.
I ended up going with Battle Born which is located in Reno Nevada, and their batteries are completely manufactured in Reno Nevada, their tech support is fantastic and they also sell a wide variety of top shelf product associated with their batteries and those products are also supported by their staff. Every person you talk to at BB is a tech support person. For purchases like this $$$$ if I cannot talk to an actual person that’s a non starter for me. BB also has a great website with blogs, and all sorts of other info.
In the thread I linked above there is a video done by an electrical engineer who tests the BB batteries under controlled conditions and compares them to their various lead acid counter parts. The one area where the lead acid batteries outperform LiFePO4 batteries is in engine starting. It’s a long vid by todays short attention span theater standards but it is comprehensive. I went with an AGM start battery, and a 100Ah LiFePO4 house battery, in addition to the three 100 Ah LiFePO4 batteries that make up my trolling motor battery.
I also highly recommend the Victron Energy IP 67 chargers, and the Victron Energy smart shunts. I was using MinnKota 10A chargers on the AGM setting to charge my batteries after a full day of use which would take 12-14 hours. With the Victron chargers my batteries are fully charged in 4 hours after an 80Ah discharge. Note, if you are not using a smart shunt you really don’t know what the state of charge is at any given point.
If you go with lithium batteries, the start, house, or both, you will have to modify your DVSR that came with your boats battery switches, this is an easy mod to make. Basically the resting voltage on LiFePO4 batteries (13.6) is higher than the close set point of the DVSR (13.2) so the switch will always be closed leaving your start and house batteries always in parallel, the purpose of the DVSR is to keep your start battery isolated from house loads. The DVSR opens when the voltage reaches 12.7 which is when a LiFePO4 battery is almost depleted. Keep in mind the DVSR was designed for use with lead acid batteries. So, you either have to hook it up on a manual switch like I did, or hook it to an ignition hot.
The LiFePO4 batteries’ performance over lead acid is stunning to say the least. If you have any questions post’em up!
