Lithium Starting Battery on a 250 SHO. Can it be regulated?

[rufuswags]

Apparently, I came in on this late for information. I just put 4 brand new Lithiums in my 2014 Cat with a 250 SHO. The lithium is a start type deep cycle battery. We still barely have ice on our lakes so I haven't had a chance to test them out yet. I am concerned since it seems like the 2014''s and earlier had overcharging problems. I saved my new 31 AGM start battery to carry around for a while just in case. Anyways, do any charging experts know if someone makes an external regulator that I could put on at my battery to make sure my voltage never goes over 14.6 volts? I emailed a company called CDI Electronics to find out if they did, but I haven't had a reply from them and that was 3 days ago. I am sure this can be done, just need to know if someone does it.

[friogatto]

The BMS will protect the battery and make sure the voltage does not exceed it's programmed limit.
With that said, when it hits over the BMS limit it will lock out the battery and the motor shutsdown.

You did not specify what Brand Lithiums. Some companies have made adjustments to the BMS to accept SHO motors.

Recommend speaking to your battery manufacturer first.

[rufuswags]

Mine is supposed to be set up to shut off at 14.6.

[rufuswags]

That being said has anyone tried to regulate alternator voltage at the battery with an external regulator? Here is a link to the company I contacted.
http://www.cdielectronics.com/blog/regulated-rectifier/

[kry29]

Personally, I dont see why that wouldn't solve the problem. I've thought of that same thing before. How would you install it? I was thinking more of a regulator that the motor cable hooks to right before it hooks to the battery or maybe right off of the alternator

[Hickory Legend]

Not a SHO guy but I have been running Lithium Pros on my last 6 boats without any issues. Not sure they arn't just trying to protect them selves if there is an over voltage issue.
I have had the BM cut the power but never had an over power issue.

[rufuswags]

Yes the BMS is shutting the battery down because it sees overvoltage. I am not even sure mine will do that because we are still under ice. Just trying to get prepared for what could happen. I will still carry my AGM start battery in the truck with me for a while until I know for sure. I should be on the water by the weekend and I will take my meter with to check things out. If anyone knows if it can be regulated at the cables where it hooks to the battery please post!

[sheeterhdip225]

When I got a Lithium battery from Lithium Pro I told them it was for a SHO and they configured it not to shutdown. It work just fine give them a call.

[rufuswags]

Mine aren't Lithium Pros. I special ordered mine and they were custom made by a very large lithium company. However, I didn't know about the SHO charging problem until after I got them and let's just say sending the battery back isn't and option. I could easily custom order one that would work, but it would cost me about $600.00. Worst case scenario I have a spare trolling battery and I put my 31 AGM back and gain 50 pounds back.

[yam911]

It is possible that a small light weight lead acid battery could be installed in parallel with the Li battery. If and when the Li shuts down due to an excess voltage situation the motor would continue to run on the lead acid battery.

[Taylor]

I think this would work and avoid the high voltage shut downs. I have a lithium promthat would shut down on high voltage. Voltage was spiking to 15+ when using the lithium batt. I changed to an optima and never saw more than 14-5 volts. Lithium Pros replaced my batt and it’s worked perfectly since. Something with the BMS was letting voltage spike. I think a small lead acid would absorb the spike and avoid the shutdown.

It is possible that a small light weight lead acid battery could be installed in parallel with the Li battery. If and when the Li shuts down due to an excess voltage situation the motor would continue to run on the lead acid battery.

[rfdong]

I think this would work and avoid the high voltage shut downs. I have a lithium promthat would shut down on high voltage. Voltage was spiking to 15+ when using the lithium batt. I changed to an optima and never saw more than 14-5 volts. Lithium Pros replaced my batt and it’s worked perfectly since. Something with the BMS was letting voltage spike. I think a small lead acid would absorb the spike and avoid the shutdown.

Taylor,

With a lead acid battery there was not overvoltage but the lithium it (sho) put out more voltage? I’m trying to decide on a lithium cranking battery and I’m seeing voltages on my AGM no more than 14.6 (supply, lowrance interface cable and volt meter at the battery) so I thought I was good. What year is your SHO?

[rufuswags]

I'm not sure if I can install a lead acid in parallel? I will contact the company I bought them from to see. In the meantime I have a request sent to Sterling battery chargers. After investigating the situation they may have something that will fix the problem at the start battery. I will let everyone know what I come up with.

[yam911]

[QUOTE=rufuswags;10141394]I'm not sure if I can install a lead acid in parallel? I will contact the company I bought them from to see. In the meantime I have a request sent to Sterling battery chargers. After investigating the situation they may have something that will fix the problem at the start battery. I will let everyone know what I come up with.[/QUOTE]

Please do.

[Taylor]

Taylor,

With a lead acid battery there was not overvoltage but the lithium it (sho) put out more voltage? I’m trying to decide on a lithium cranking battery and I’m seeing voltages on my AGM no more than 14.6 (supply, lowrance interface cable and volt meter at the battery) so I thought I was good. What year is your SHO?

My SHO is a 2017. I watched it closely with a digital volt meter and even switched the lithium pro to my other boat that has a Suzuki 140. I saw the same voltage spikes causing the BMS to shut down. On both engines I never saw above 14.5 with an Optima. I dont think it was the battery putting out more voltage. I think the alternator tries to regulate to 14.5. Once the batt is fully charged, the alternator reduces its output. My theory is that on a lithium, the battery is very efficient and sometimes that allows voltage to spike quicker than the alternator has time to react to cut back the voltage output. I was seeing voltage spikes above 15 volts but also checked amp output from the alternator back to the battery and it was very low (.2 amps) feeding back to the battery. On the lithium that .2 amps would spike the voltage. On the optima, I still saw the .2 amps once the batt was fully charged, but I think the battery could “absorb” that amperage without spiking to higher voltage. As mentioned, once Lithium Pros swapped out my starting battery, everything worked perfect and I never see above 14.5-14.6 volts. I think they mentioned the BMS on my old batt had a problem.

[rufuswags]

Ok, I got a reply from the lithium company and they said I cannot run a lead acid or agm in parallel with my lithium start battery to avoid a shutdown. That being said I was finally able to find a lake with no ice today to fish and test out my new batteries. I backed the boat in and I hit the key to start my SHO and the battery immediately shut down and did not turn back on. Fortunately, I had my Duracell 31 AGM with me and I swapped it out and all was well and the SHO lit right up. I now was concerned about my 3 lithium trolling batteries which are the same battery as the start battery. They were all at 83% when I started fishing. I fished a total of 6 hours and at the end of the day I still had 80% in them so they worked awesome! The start battery did not turn back on until I hooked it to my Dual Pro charger when I got back home. Is there a way to turn the battery back on on the water? I am new to lithium. I will contact the manufacturer to see if I can get this problem fixed with the start battery. In the meantime it looks like I have a spare trolling battery lol

[rufuswags]

The company contacted me back and are sending me a new case and a BMS that will work with my SHO. I am not sure yet what that entails I will keep anyone interested informed.