2nd battery on a 266RKS

[Bobstekeur]

I’ve got on battery on the a frame just in front of the compartment for the propane tanks. Looking to add a 2nd battery but there’s not a lot of room. Anyone mount a 2nd battery on the outside? At some point I may switch to lipo’s but not ready for that expense, I’d like to add a 2nd deep cycle battery as that what I have now.

[GHen]

How old is your current battery? More than a few months?

It is “highly” suggested that both batteries be the same age, brand and type. Your charger will only charge up to the weakest battery.

With the expense or a new mount, battery box and two new batteries, you should consider just one lithium now if you’re even remotely thinking about it. The costs have dropped dramatically.

[Bobstekeur]

Originally Posted by GHen

How old is your current battery? More than a few months?

It is “highly” suggested that both batteries be the same age, brand and type. Your charger will only charge up to the weakest battery.

With the expense or a new mount, battery box and two new batteries, you should consider just one lithium now if you’re even remotely thinking about it. The costs have dropped dramatically.

Good point, the battery came with the rv so no telling the age. I know you can’t put lead acid inside so it looks like I’ll be looking at lithium. I’m not looking at having a lot of power, enough to keep the lights on, run the refrigerator on propane and charge phones and iPads when we don’t have shore power. I’ve been looking at a 200watt portable solar setup to keep the batteries charged

[Bobstekeur]

Originally Posted by GHen

How old is your current battery? More than a few months?

It is “highly” suggested that both batteries be the same age, brand and type. Your charger will only charge up to the weakest battery.

With the expense or a new mount, battery box and two new batteries, you should consider just one lithium now if you’re even remotely thinking about it. The costs have dropped dramatically.

The more I look into changing batteries the more questions I come up with. I’m looking into getting 2 100 amp hour lifepo4 batteries. I’m new to all this but as I understand it the battery is charged from the rv when I’m plugged into power and from my truck when I’m towing. Will the lifepo4 batteries be charged the same way with the same wires I have connected to the lead acid battery?

[BC_Trev]

Your best bang for your buck is going to be Trojan T105's. 2 6v golf cart batteries in series for 225Ah's. Is lithium better? Yep, but your going to be paying 2-3 times the cost for not 2-3 times the benefit. Unless you have already upgraded everything else in your rig, save that $$$ for other upgrades (solar, proper chargers, etc).

[HAL9001]

Originally Posted by BC_Trev

Your best bang for your buck is going to be Trojan T105's. 2 6v golf cart batteries in series for 225Ah's. Is lithium better? Yep, but your going to be paying 2-3 times the cost for not 2-3 times the benefit. Unless you have already upgraded everything else in your rig, save that $$$ for other upgrades (solar, proper chargers, etc).

When crunching the numbers on LiFePO4 vs lead-acid batteries, always keep in mind that the service life of a LiFePO4 is often 2X that of a lead-acid.

Additionally, you'll get a much higher depth of discharge than lead-acid batteries, nearly 100% vs 50%. That's much better usable power for the money.

Given that the cost of LiFePO4s have come down considerably, anyone wanting to replace their lead acids would do well to consider them.

The only major caveat is if you need to recharge a battery below 32 degrees F. You should never charge a LiFePO4 below freezing. However, some LiFePO4s now have built-in heaters for this and you can add external heaters to those that don't, so that limitation can now be overcome.

[Smabernethy]

Just put a 2nd battery on my 2021 330rsts.... in the front near propane tanks...... I bought a Camco dual battery box and wired the 2 batteries in parallel

[Bobstekeur]

Originally Posted by Smabernethy

Just put a 2nd battery on my 2021 330rsts.... in the front near propane tanks...... I bought a Camco dual battery box and wired the 2 batteries in parallel

I’d be interested in seeing what it looks like, I don’t have a lot of room on the front of the frame. I called the company that makes the converter and found it doesn’t support lifepo4 battery’s but it can use AGM batteries. I’d like to get 2 100amp hour Agm’s which with portable 200 watt solar panels for the times we’ll be boondocking should keep me in power. I have a 5500 watt generator but want to use that as a last resort.

[HAL9001]

Originally Posted by Bobstekeur

I’d be interested in seeing what it looks like, I don’t have a lot of room on the front of the frame. I called the company that makes the converter and found it doesn’t support lifepo4 battery’s but it can use AGM batteries. I’d like to get 2 100amp hour Agm’s which with portable 200 watt solar panels for the times we’ll be boondocking should keep me in power. I have a 5500 watt generator but want to use that as a last resort.

LiFePO4 batteries can use a converter designed for lead-acid batteries provided it does not have an automatic equalization cycle. A converter designed only for lead-acid batteries won't be ideal for an optimum LiFePO4 charge cycle but it won't hurt them either. The LiFePO4's BMS will protect it from most issues.

Also, keep in mind that a converter designed for lead-acid batteries can be replaced with one also designed for LiFePO4s. It would be a good upgrade and should not stop anyone wishing to convert to LiFePO4s.

For most battery upgrades (except possibly for constant below freezing weather applications) a LiFePO4 upgrade is usually the best choice financially and for the best performance. It may cost more upfront, but you'll save in the long term all the while enjoying much better battery performance and longevity as well as a significant reduction in weight.

[Bobstekeur]

I replaced my converter with one that can supply a constant 14.6 volts to charge lifepo4 batteries. I have a 200ah battery coming Friday and my plan is to mount it under the bed in the front of the RV. I also got a battery meter with a shunt to keep track of the battery usage. I figure with a 200 watt portable solar panel I should be able to stretch by boondocking days to quite a few days