Lithium batteries in a Trend 23L (or Viva 23L)?

[davedutah]

Has anyone with a Trend or Viva 23L thought about adding a lithium power system?

[davedutah]

I've just bought a 2015 Trend 23L. I'm sure the original, single, group 31 AGM battery is not going to make me very happy. I'm considering a couple of Battle Born 100Ah (usable, per battery) drop-in replacements (https://battlebornbatteries.com/shop...cycle-battery/), but the location of the battery tray under the coach, next to the engine muffler does not seem like an ideal spot for $2K worth of temperature-sensitive batteries. I'm thinking of putting them under the bench near the door, in the indoor/outdoor storage compartment. Or maybe one or two of the Renology 170Ah batteries in the same spot (https://www.renogy.com/renogy-lithiu...12-volt-170ah/).

I'm wondering if the Trend's Power Center is compatible with charging these batteries and if the engine alternator would be good at replenishing them to minimize the generator needing to do so.

[BBQ]

.

Have you checked with the Trend Facebook group?
They might be able to give a better answer to model specific questions.

[cruising7388]

Originally Posted by davedutah

I've just bought a 2015 Trend 23L. I'm sure the original, single, group 31 AGM battery is not going to make me very happy. I'm considering a couple of Battle Born 100Ah (usable, per battery) drop-in replacements (https://battlebornbatteries.com/shop...cycle-battery/), but the location of the battery tray under the coach, next to the engine muffler does not seem like an ideal spot for $2K worth of temperature-sensitive batteries. I'm thinking of putting them under the bench near the door, in the indoor/outdoor storage compartment. Or maybe one or two of the Renology 170Ah batteries in the same spot (https://www.renogy.com/renogy-lithiu...12-volt-170ah/).

I'm wondering if the Trend's Power Center is compatible with charging these batteries and if the engine alternator would be good at replenishing them to minimize the generator needing to do so.

The shore side battery charger would have to be changed out for one set up for charging lithium batteries. The alternator certainly will charge the lithium batteries but the problem is that the regulator is set up for absorption charging and will continue to charge the battery even when the battery is fully charged. This is not good for any battery but the AGM you have in place is less likely to be damaged by long term overcharging than lithiums.

IMO you will be money and aggravation ahead by sticking with AGMs. Lithiums certainly rank high for power density and depth of discharge but paradoxically they are much more fragile than AGMs with respect to temperature and require a complex management system to keep them happy. If space permits I think a couple of Lifeline 31XTs will provide you with the battery reserve you need and will be maintenance and aggravation free.

[peteco]

Good discussion here about adding lithium in conjunction with existing system. I am considering this on my 2006 Roadtrek 210.

http://www.classbforum.com/forums/f2...html#post77471

[davedutah]

Originally Posted by cruising7388

The shore side battery charger would have to be changed out for one set up for charging lithium batteries. The alternator certainly will charge the lithium batteries but the problem is that the regulator is set up for absorption charging and will continue to charge the battery even when the battery is fully charged....
Lithiums ... require a complex management system to keep them happy. If space permits I think a couple of Lifeline 31XTs will provide you with the battery reserve you need and will be maintenance and aggravation free.

Sure, but some of the lithium batteries come with integrated battery management systems in each battery, like the Battle Born 100Ah which are designed as a drop in replacements for Group 31 AGM sized batteries (though I would install them inside for temperature protection). The Battle Borns have twice the usable amp hours for half the weight (and are rated for many times the number of charge cycles of AGM).

However, the existing charger still usually needs to be reprogrammed for the different voltage thresholds used by the lithium batteries. I'm mainly wondering if anyone has done so with the existing one in the Trend or Viva 23L, and if so, how easy was it?

[booster]

Originally Posted by davedutah

Sure, but some of the lithium batteries come with integrated battery management systems in each battery, like the Battle Born 100Ah which are designed as a drop in replacements for Group 31 AGM sized batteries (though I would install them inside for temperature protection). The Battle Borns have twice the usable amp hours for half the weight (and are rated for many times the number of charge cycles of AGM).

However, the existing charger still usually needs to be reprogrammed for the different voltage thresholds used by the lithium batteries. I'm mainly wondering if anyone has done so with the existing one in the Trend or Viva 23L, and if so, how easy was it?

As always, I will say that you have to be careful with the claims of the "drop in" lithium batteries. Unless they have fixed it lately, the Battleborn site is full of technical errors and erroneous claims to make themselves look better and AGM batteries worse. They appear to be made by Dragonfly which has been around for quite a while but didn't get much market. The BMS in drop ins is usually very basic and not all that protective, from what we have been able to find, and has no output so you don't have any way to see what is going on, even for state of charge. There is also the waste of buying multiple BMS systems that aren't centrally controlled/



Several manufacturers have tried using drop-in lithium in their RVs and have quickly gone away from them. Some people have used them and had good luck, though.


If I were considering a lithium system, I would first look at a system line the Elite kit that is mentioned further up on this thread.


There are lots of things to consider with lithium as you need to have the charging sources disconnect when the batteries are full for all of them but still reactivate when charging is needed or to recover from a low voltage or low temp shutdown. You can't charge under freezing, but can use down to about -4F per the latest we have heard but some dispute. You have to have heaters, of course, for the batteries, and the power to run them if the batteries are offline.


Basically, this is not a "drop in some batteries and reprogram the charger" installation IMO.


There are lots of discussions of systems on this forum, both factory and home built, which will give you lots of information.







A

[davedutah]

Do you know if the batteries Elite uses are the more stable LiFePO4 batteries? Their site just says "Lithium Ion" and separately mentions "phosphate technology" but doesn't specifically say, anywhere that I can find, that they use LiFePO4 or "Lithium Iron" as it is often referred to.

[booster]

AFAIK all the Elite batteries are LiFePo4