Recent content by Visionquest

After much research, design and building my 12v LifePo4 upgrade to replace my two 6v AGM's in my RV is now complete and ready to install. I am very happy with the result and it will be interesting to see how it does through next winters' storage monitoring. I've attached my design file and...

I won't be heating the cells past 45-50 degrees F. The wattage of the heat pads will be around 20 watts total spread across the sides and bottom. I don't want to create hot spots which is why my original questions focus on use of an aluminum plate in contact with the heat pads. I think its...

I expect no more than 100 degrees F on the pads though designing for somewhat higher will be a good idea. Maybe 150. I just ordered poron sheets from mcmaster for another application so I'll take a look through their catalog. Good suggestion.

I like your setup though I plan to do something different. Thanks for sharing, unfortunately it doesn't help answer my questions.

What kind of still foam will be ok long term with direct contact of the heat mats?

I have done rather extensive reading on the subject of heating pads for LifePo4 builds. I'm not finding quite enough specific information to complete my 12v design, hence this new thread. This build will be 12v 302aH using EVE cells. I will be using 25watt silicon heater mats that many others...

Yep, that particular controller is all wrong for the battery application. A PWM approach to controlling heating pads would definitely work but the control circuit likely not worth inventing. So....I'm convinced to keep it simple and ordered my heat pads and temp controller. But doing...

Interesting find! Concept could be used for sure.

Thanks for that link. Great summaries of available gear. Interesting comment about cold weather charging using low currents.

I am really impressed with Overkill. Just wish they made a 200amp BMS since I want more peak current for confidence in starting my Onan5500. The JK spec's 350amp short term.

At the moment I am leaning towards the JK because Overkill only has up to 120amp and the JK seems to be the only one with adequate active balancing without adding anything. However, you input is the first I've read about quality concerns with JK. Can you tell me a bit more about the failures?

Thanks. I did find many of those search link but your query has a couple more. The Overkill BMS documentation is great. The only think I'm concerned about is that it uses passive balancing. The JK uses 1 or 2 amp active balancing which is desireable from what I've read? Can I get your...

Picking a BMS is the last step in my 12v battery project. I will be using 304 aH cells from EVE. From everything I've read getting a high balance current spec (1 - 2 amps) and overall high current spec (200 amps) is my best bet. I also definitely want bluetooth connectivity. I'm trying to...

Thanks. That is a pretty handy calculator, but I'm not certain I understand how to use the number. The text says to multiply by wattage of the solar panel but how does that make sense. The chart gives kwh/m2/day. If I assume 15% solar efficiency of the panel, and the panel is 58"x 26" that...

I'm close to completing design research for my 12v DIY battery. In this thread I will summarize my analysis of the heater wattage needed based on my worst-case use case of off-grid winter RV storage. I need that batteries to stay active enough to run a remote monitor system. My Requirement...