Thinking of converting to Li ion batteries

JoeC · 09-26-2018, 07:31 AM

Battery boost solenoid will be connecting the lead acid chassis battery with the new Li ion batteries which is not a good thing long term; momentary switch-initiated battery boost connections when needed should be fine. However, connecting these batteries while driving, which is the normal, is not acceptable and may be harmful to the very expensive Li ion batteries.

I want to be able to disable the activation of the boost solenoid only while driving or when the ignition switch is in the "on" position but still have the switch work manually when needed. If someone knows how to do this I would really appreciate the help. Also, if someone knows how to remove the battery boost switch from the dash on my 2015 Itasca Spirit (Mini Winnie) Class C Ford E450 chassis, that would be very useful too.

As a side note, I have ordered an Amp-L-Start charger by LSL Products to charge the chassis battery while plugged in to shore power or when the generator is running. This seemed like a good idea as I use the satellite radio in the dash a lot while camping. This will keep the chassis battery charged so I won't need to use the battery boost switch and probably extend the life of the battery too.

**creativepart** · 09-26-2018, 08:52 AM

I’ve read a lot about RVers adding Li batteries but I’ve not seen anyone talk about the RV’s motor charging system being detrimental to them. I’m not saying it’s not so, but it’s odd that it doesn’t come up much, if at all. Maybe I just have missed those discussions.

Seems like a new voltage regulator tailored for Li use should be available for the RVs charging system.

JoeC · 09-26-2018, 06:09 PM

I know, but ignorance is bliss. All Li ion battery and charger manufacturers all say the same thing; don't mix these battery types as they have different charging needs and vulnerabilities. I'm not willing to gamble $2,000 to see who is correct. Wait about 5 years and see if anyone is crying that they destroyed their expensive batteries and nobody warned them. Did they ask? Or did they just design the system on their own? Time will tell.

**creativepart** · 09-26-2018, 07:46 PM

Mixing two types in the same bank I 100% agree. What I don’t think is having a chassis battery of one type and house batteries of another is what they are talking about. Why not call the battery supplier and ask them?

JoeC · 09-26-2018, 08:25 PM

I have checked with the battery manufacturers who have reservations. Problem arises when underway the alternator becomes the charger for the combined battery banks through a continuous duty solenoid. The alternator charging system has little intelligence and is not designed to charge Li ion batteries. I am looking to disable the solenoid while underway solving the problem. I need to be able to get at the wiring behind the "battery boost" switch which is likely being used to route the ignition power to the solenoid through normally closed contacts, otherwise, there would be 2 wires going to the solenoid, but there isn't. Just turning the key to "on" energizes the solenoid. Battery charging systems are much more complicated than most people realize.

jerichorick · 10-03-2018, 02:29 PM

Quote:

Originally Posted by JoeC

Battery boost solenoid will be connecting the lead acid chassis battery with the new Li ion batteries which is not a good thing long term; momentary switch-initiated battery boost connections when needed should be fine. However, connecting these batteries while driving, which is the normal, is not acceptable and may be harmful to the very expensive Li ion batteries.

I want to be able to disable the activation of the boost solenoid only while driving or when the ignition switch is in the "on" position but still have the switch work manually when needed. If someone knows how to do this I would really appreciate the help. Also, if someone knows how to remove the battery boost switch from the dash on my 2015 Itasca Spirit (Mini Winnie) Class C Ford E450 chassis, that would be very useful too.

As a side note, I have ordered an Amp-L-Start charger by LSL Products to charge the chassis battery while plugged in to shore power or when the generator is running. This seemed like a good idea as I use the satellite radio in the dash a lot while camping. This will keep the chassis battery charged so I won't need to use the battery boost switch and probably extend the life of the battery too.

Have you looked at the Winnebago resources for your 12V wiring? https://winnebagoind.com/

JoeC · 10-03-2018, 10:22 PM

You can't change the voltage regulator on the alternator to Li ion as the starter battery is most likely lead acid. It's crazy expensive to use a Li ion battery for a starter. The battery charging systems in the RVs are designed to charge lead acid batteries because that's what's out there and has been for decades. Lithium ion batteries are relatively new to the RV after-market and not likely available as original equipment, even on the high-end rigs. Why spend all this re-engineering for a really expensive system that nobody really needs if they only go from one plug-in to the next, as most RVers do?

JoeC · 10-03-2018, 10:43 PM

I have checked into the Winnebago 12 VDC drawings, they show very little and do not include wiring data anymore. I have a 2015 Itasca Spirit 27QP. There is a nice detailed drawing of the switch (exposed front side) and other physical parts, nothing else useful. I'll bet money that there is a battery wire and an ignition wire going to the battery boost switch. Ignition goes through the normally closed contacts which energizes the solenoid when the ignition switch is turned to "on". The battery wire goes to the normally open contacts which energizes the solenoid when the battery boost switch is toggled. Simple. I just can't get at the wires to disable the ignition wire and keep the alternator from trying to charge the coach batteries, if they are Lithium ion. They will only be charged through the shore power or generator and the Li ion power converter / charger. Everybody wins. I will be adding a small charger for the starter battery that will run off shore power or generator. Just another "option" that should be standard equipment.

mikf · 10-07-2018, 05:36 PM

Pleasureway Rvs have 2 100ah eco-ion batteries that charge when the engine is running. Not sure how they do it, but there is no battery boost switch.

JoeC · 10-07-2018, 06:11 PM

Quote:

Originally Posted by creativepart

I’ve read a lot about RVers adding Li batteries but I’ve not seen anyone talk about the RV’s motor charging system being detrimental to them. I’m not saying it’s not so, but it’s odd that it doesn’t come up much, if at all. Maybe I just have missed those discussions.

Seems like a new voltage regulator tailored for Li use should be available for the RVs charging system.

lithium ion batteries are relatively new and I don't know of any manufacturer putting them in RVs as standard or optional equipment probably because they present a few challenges and are very expensive. Most RVers are well served by the standard lead acid batteries.

WFCO has just come out with a power converter / charger for lithium ion coach batteries that is available by special order through Camping World. Using the original power converter / charger will work except that you will only charge your Li ion batteries to about 95% at best. The bigger issue is that the alternator / voltage regulator is old technology and not very smart, therefore it is very likely to supply the wrong voltage at the wrong time for Li ion batteries. At $1,000 a piece for Li ion batteries, I'm not willing to gamble with charging these things.

As for those who are running on Lithium ion batteries today and haven't addressed the alternator charging issue, time will tell.

JoeC · 10-07-2018, 06:27 PM

Quote:

Originally Posted by mikf

Pleasureway Rvs have 2 100ah eco-ion batteries that charge when the engine is running. Not sure how they do it, but there is no battery boost switch.

Thanks for the input. Pleasureway (Class B? I'm not sure). I haven't studied their battery charging design. Something to do in my spare time.

The whole battery system could be all Li ion and the alternator is designed for those batteries. Battery boost is not necessary if you are running all batteries connected. Another possibility is that the starter is lead acid and kept separated but the alternator power is conditioned by an intelligent device (they do exist, check with Victron) that supplies the correct charge power to the Li ion batteries.

Don't hold your breath waiting for Winnebago to come out with Li ion coach batteries any time soon.

mikf · 10-07-2018, 06:48 PM

Quote:

Originally Posted by JoeC

Thanks for the input. Pleasureway (Class B? I'm not sure). I haven't studied their battery charging design. Something to do in my spare time.

The whole battery system could be all Li ion and the alternator is designed for those batteries. Battery boost is not necessary if you are running all batteries connected. Another possibility is that the starter is lead acid and kept separated but the alternator power is conditioned by an intelligent device (they do exist, check with Victron) that supplies the correct charge power to the Li ion batteries.

Don't hold your breath waiting for Winnebago to come out with Li ion coach batteries any time soon.

The starting battery is still lead acid. I have never seen a wire schematic for Pleasureway.