Valence XP Super Thread

[karlbar2k]

Yeah £500 each is way over the top but hey they are yours to do with as you wish , I got mine on eBay at a very keen £90 a battery I bought 10 , I wish I’d have bought more but I wasn’t sure if they would be useful at the time of purchase.
Are yours the u27-36xp batteries ? Fancy putting up a picture or two ?

Really wish I could find the u27-36xpd for £90 each at the moment.

 

[matt D]

Yeah , I’ve just bought 6 more from eBay , had to pay more for those , £800 so £133 each which is still cheap given what they are capable of . The 6 I’ve just purchased actually originated from the same place but passed through a few peoples hands after so I’m glad the batteries are the same age and I think they’ll perform the same as my original 10 .

 

[martinwinlow]

Hi All,

I have 4 XP27s in parallel at my cabin with solar charging and generator if needed. Lately they get down to 12.9v in morning before sun hits. Are they being hurt by this?

Paul

A bit late but no, their safe cutoff discharge voltage is 10.0V - so oodles of room... I would not have thought they are even half discaharged at 12.9V...

 

[martinwinlow]

Forgive me but I do not want to read through this entire (enormous) thread but would be interested in a *cheap* ('ish) solution to the issue of monitoring a bunch of U27-12XPs all at once rather than having to do them one at a time via the Valence diagnostic app...
Anyone got any links to something, please?
MW

 

[Cloroxbottle]

I have a bank of three U27-12XP batteries wired in parallel.

I'm trying to set up a Mastervolt Powercombi-12-1200-50 inverter charger's settings to work with this bank.

The variables I can control are bulk charge voltage, bulk charge time, absorption charge voltage, absorption charge times, float charge voltage and equalization voltage, undervoltage protection, and overvoltage protection.

The undervoltage I've turned up to 12, decreased overvoltage to 15, and set equalization at 12.0 since I apparently can't turn it off.

I increased bulk voltage to 14.4, set absorption at 14.2, and set float at 13.6

Finally, the "times" are throwing me for a loop as I thought that these modes were dependent on depth of discharge. The defaults are 4 hours for bulk, 2 for absorption. Leave those alone? Change them? Divide battery capacity by the voltage selected for the modes and calculate bulk time to be 90% of that and absorption to be 10%? Not sure what to do about those two settings.

 

[DavidM64]

Total newbie here so apologies for my ignorance. I am wondering if a Valence U27-12XP can be used as a house battery in an RV and charged off the alternator or shore power? Can it be used in series or parallel with a Pb-acid battery? I cannot get any help from Valence/Lithion and am not an engineer (or even close). I do NOT have a solar hookup. Also I don't have a controller and am not sure how complete the ones on eBay are. Any help appreciated? Experts please have mercy on a newb! @Travis

 

[martinwinlow]

Total newbie here so apologies for my ignorance. I am wondering if a Valence U27-12XP can be used as a house battery in an RV and charged off the alternator or shore power? Can it be used in series or parallel with a Pb-acid battery? I cannot get any help from Valence/Lithion and am not an engineer (or even close). I do NOT have a solar hookup. Also I don't have a controller and am not sure how complete the ones on eBay are. Any help appreciated? Experts please have mercy on a newb! @Travis

Hi David, A bit late in the day but:
1/ Do *not* use your U27-12XP in anyway with a lead-acid battery. Doing so will make it very difficult to protect either battery adequately from over/under charging.
2/ Yes you can use the U27-12XP as a 'house' battery but I'd say one module is not enough for any realistic use unless you are *purely* powering LED lighting from it (mobile phone charging, too) and not very much at that.
Essentially you must simply (but very effectively) protect the U27-12XP from being discharged lower than 10V and from being charged to more than ~14V. There is a lot of talk about the need for balancing etc but, in my experience, as long as you avoid (like the plague) the extremes of SOC, these batteries are nigh-on bulletproof. The same cannot be said of any other Li battery chemistry than basic LiFePO4 - as these modules are.
Therefore, any run-of-the-mill 12V charger *can* work but just be sure that it does not take the module higher than 14V - and most designed for lead-acid almost certainly will on their own. You could combine one with an additional circuit to cut power to the charge when it gets to 14V - plenty of kit out there to do that. But I'd be inclined to add at least some level of redundancy to that as well as an alarm should that system fail and the charging voltage rise higher than 14V (or whatever V you choose).
Likewise from an over *dis*-charging POV something like the Victron 'Battery Protect' would be useful but again, I'd be looking for at least a second layer of protection and, again, an over-discharge alarm.

 

[meganet]

Hello,

I have a few U27-24XP and not able to read them with the 12.12 software. It is a different one? Wonder because the software only shows up to 6s and the 24v are 8s modules. The BMS on them are different than the 12v model pictures.

Thanks