StirCrazy wrote:



Lots of let you adjust some parameters with the blue tooth now as the blue tooth is part of the BMS, they just lock out the settings they don't want you to play with when they design the app that is used to connect. so, for instance, I bought the JBD BMS for my battery and using its native app I can alter any BMS setting, but if I was making them and selling them, I would make my own app designed off the native JBD but lock out any setting that is there for the safety of the battery like the low temp cut off for example. others I might limit the range it can be adjusted within. all easy enough to do if you're an app designer.

3 tons wrote:



Please clarify, such BMS programmability has not been my experience having had two different drop-in LFP’s…Perhaps you’re referring to a homebrew, or maybe suggest a drop-in brand that has programmability?

3 tons

StirCrazy wrote:



lots of "drop in" LFP use the exact BMS I have, well maybe lower amp ratings. like I said they may customize the interface so you can't access specific things, but you can still monitor and usually you can set your own numbers for cold charge protection, bottom and top cutoff and such, they will just limit it so you can only change those numbers to the safer side of the scale instead of something that can damage the battery. If they are advertising "Bluetooth or wifi" connectivity there is a chance you can do what you want if you can get the native app to work in place of the modified app. so, home brew or not if they are using the Bluetooth BMS, they can be adjusted through that, unless they modify the app so it can't be. Like I have said, I have seen reviews of some that are a monitor only limitation that is done through the actual hardware, but those you can still get into with a physical cable if you open the cover up. Others I have seen a range now of limited setting capability, to monitor only done through the app which can be worked around as it is a Bluetooth connection. You just need the connection info from their app then figure out which app they used and modified and get that and connect. Would I recommend this to anyone, not really unless you were out of warranty and knew what you're doing.

3 tons wrote:


Got it, kinda interesting…FWIW, my drop-ins are tamper-proof - but either way, since mine came with a 10yr warranty I’m happy to leave the experimentation option to the more capable and adventurous

3 tons

Itinerant1 wrote:

Just curious if the batteries are working with the predetermined settings in the sealed box why would you want to experiment with them?

Itinerant1 wrote:

Just curious if the batteries are working with the predetermined settings in the sealed box why would you want to experiment with them?

StirCrazy wrote:



easy cycle life. if I can change the top and bottom from 0 to 100% to 10 to 90% that can take your average LfP from 3500 cycles to 4500 to 5000. then if you operate in the top 3rd of that you can go even higher. If I knew I could get into a battery like a chins I may have bought them instead of making my own just to be lazy, but I use the settings in my Bluetooth quite a bit. I have 3 profiles on my phone for setting the BMS, I have a storage routine where the BMS will only charge the cells to 65% of the capacity then won't recharge until they drop below 30% as well my cold temp cut off is bumped up to 3C to be safe. I have a "getting ready to go camping" setting where it sets the bottom at 10%, puts the cold temp cut off back to 1C and charges to 100%. then I have a "camping" setup where the only difference is I lower the top to 90%.

I can limit the battery as I have a 10-day capacity without the solar and unlimited time with the solar, so I decided to make the battery last a bit longer and sacrifice about 2 days' worth of capacity. The batteries are top balanced and topped right up whenever I leave the house on a camping trip.

So basically, cycle life, and the ability to be over cautious on some of your safety settings is the reason.

3 tons wrote:

Interesting FWIW, what you’re describing is pretty much how I opt to cycle and charge my drop-in LFP’s.

Before departing, I fully charge and balance the two 200a/hr paralleled batteries, but after that they tend to kinda float off of solar harvest, routinely cycling them (harvest dependent…) from about 80-90’ish% SOC, to something lower and then back again…After about 4 or so ‘less that full recharge’ cycles, I typically opt for another 100% full recharge to restore proper cell balance and to address cumulative metering drift…A voltage programmable solar controller (with programmable ‘post full charge’ time-out) makes unattended charging an easy option (i.e. avoiding the possibility of an over charge…)…Since there’s really no absorption phase, just a single voltage, and no real need to routinely fully re-charge, charging has proved to be uber straightforward and uncomplicated…

3 tons