Mixing batteries Start v House

[DRock3d]

I have a TPPL AGM group 31 house battery that has been great, I can never drain it on the water. It's heavy as can be and makes my boat list pretty heavily to that side. I've been running a group 24 lead acid as the start battery and it's finally time to replace it

Is it an issue to run different sizes for start/house?

Any recommendations on a lightweight start battery?

 

[cwoav8r]

Is it an issue to run different sizes for start/house?

FWIW that is how my setup has been since 2008, never had an issue. I LOVE my BlueTop, I can't kill it... that battery has to be at least 8 years old if not more and I have run it dead several times.

Any recommendations on a lightweight start battery?

I'll let the others chime in... I myself would steer clear of LiPos, but that's just me. I have always preferred lead acid for the crank battery, but I will look at alternatives when I need to replace it.



Yea, I know... I'm still cleaning the boat...

 

[FSH 210 Sport]

If you want a lightweight starter battery the a lfp battery is your only choice. But you will have to use a “starter” battery not just a deep cycle. The issues with the LFP batteries used as start batteries have been corrected with start type
batteries.

DL+ 12V 60Ah Dual Purpose 1000CCA LiFePO4 Battery

Twoin pack, 12V 60Ah multi propose 1000 CCA lithium starting dakota battery plus for marine engine, automotive, deep cycle use. 8x longer 11year lifetime.

dakotalithium.com

DL+ 12V 135Ah Dual Purpose 1000CCA LiFePO4 Battery

DL+ 12v 135Ah LiFePO4 Golf Cart & 1000CCA Automotive Battery. Marine & Automotive Compatibility. 135 Amp Hours of deep cycle Dakota Lithium performance.

dakotalithium.com

12V 100Ah Deep Cycle Heated LiFePO4 Battery

The 12v 100Ah Lithium Battery deep cycle, offers reliable power for marine, solar, & off-grid systems. Lightweight and built for long-lasting use.

dakotalithium.com

But, as discussed my battery upgrade thread and many others, you will have to modify your dvsr to only be active when the engines are on to use a LFP battery.

If you want to get rid of the list caused by the big heavy AGM battery then going to a LFP house battery will solve that as well.

 

[anmut]

No, fine to mix. My two house batteries are X2 AGMs, and my starter is an Interstate standard lead acid.