What is Best Way to Add a Second Solar Panel and Upgrade Charging System for Odyssey TPPL Batteries?

Updated 12/17/2025 | Published 12/15/2025

Products Featured in This Question

Go Power Overlander Expansion Kit - 200 Watt Solar Panel

(129)

$375.80

Go Power MPPT Solar Charge Controller - PowerTrak - 12V and 24V - 30 Amp

(1)

$227.99

Progressive Dynamics 9300 Series RV Converter Charger - 12V - 60A

(372)

$289.23

Question:

RV currently has roof top 160W solar panel, Zamp 30A controller, 120VAC converter, two Odyssey TPPL batteries. Want to add additional roof panel and replace controller/converter with ones that supports TPPL charging. What are your recommendations?

asked by: Jonathan S

Expert Reply:

Hello Jonathan,

Thanks so much for reaching out. Since you already have a 160 watt roof panel and Odyssey TPPL batteries, adding another panel and updating your charging equipment is a great idea. For the solar side, I recommend the Go Power Overlander Expansion Kit with the 200 watt panel, # 34282182. This lets you keep your existing 160 watt panel and simply add the new one to the roof.

If you wire the two panels in parallel, the system will operate at the level of the smaller panel, so you’ll get about 160 watts from each for a combined output of roughly 320 watts. To get the full 360 watts from both panels you would technically need a separate controller for each one. That said, the real-world charging speed difference between 320 watts and 360 watts is usually small. On a sunny day, the difference is often only a few extra minutes of charging time to top off the batteries, so if it were me, I would keep things simple and just wire the panels in parallel.

To get the best performance from the combined array, I suggest upgrading to the Go Power MPPT Solar Charge Controller, # GP32QR. It’s much more efficient than your current PWM controller and has an AGM setting that works very well with Odyssey TPPL batteries. This will help you get the most out of the available solar power, even in partial sun.

For shore-power charging, the Progressive Dynamics 9300 Series 60 amp converter, # PD79RR, is a great match. It provides the proper charging voltages that Odyssey batteries prefer and will charge them faster and more accurately than older converters. This helps maintain battery life and ensures you’re getting full capacity when you need it.

The last upgrade I’d suggest is replacing your existing converter with the Progressive Dynamics 9300 Series 60 amp model, # PD79RR. This converter provides the proper charging voltages that Odyssey batteries like, especially during bulk and float charging. It helps keep the batteries healthy, charges them faster when you’re plugged in, and prevents undercharging, which is common with older converters.

Are you looking to add more panels to get ready for more boondocking type of camping? The best views are usually the ones on the road less traveled! What was your greatest adventure of 2025?

expert reply by: Kate F

Back of Go Power/Dometic Controller
(click to enlarge)

Jon S.

12/15/2025

Kate, thanks for responding promptly and providing very good recommendations. This is on a 2017 Arctic Fox 27-5L 5th wheel which we bought new and are the original owners. Except for the batteries, the rest is OEM. The Odyssey batteries I installed in Nov 2021 and, up to very recently, have not had a problem keeping them charged. We were boon docking in the Smoky Mountains with the temperature in the 20s and the batteries dropped to almost 100% discharge which got me thinking about my equipment. Being Odyssey batteries, they were not damaged and I was able to fully recharge when I got home using a BatteryMinder charger. We have put over 50K miles on this camper and have had our share of excitement over the years. But you asked about 2025. This summer, we added another 8000 miles on it by going to Canada via Niagara Falls, across to Nova Scotia, down to New Jersey, and back to Tennessee. Mostly E/W, a couple of full hookups, and some boon docking

Kate F.

12/16/2025

@JonS Wow Jon, it sounds like you’ve had some amazing adventures in that Arctic Fox. A trip through the Smokies, then all the way up to Niagara Falls, Nova Scotia, down to New Jersey, and back to Tennessee… that’s a serious journey. What a fun way to put miles on the camper. It’s also great to hear how well your Odyssey batteries bounced back after that deep discharge in the cold. Those temps in the 20s are no joke, so their recovery says a lot about the quality of those TPPL batteries. With the upgrades we talked about, you’ll have an even better setup to support more boondocking and long hauls like that. I hope you have a wonderful Holiday Season with your most favorite people, and may 2026 be filled with awesome adventures =)

Lee

12/17/2025

@JonS Hi Kate.You can reach out to Jonathan and tell him that the 2nd 200 watt solar panel on my Go Power system makes all the difference in the world. The installation was straightforward and very neat.Thanks.Lee