So everywhere you read it says NO!

 

but when I look at the charging cycle of the MXS5.0 then is seems (when using normal cycle) to be a perfect fit for the Blue Nova 12v.

 

Blue Nova 108 ah 12v...  edit.. sorry 104 wh..  so small alarm system type battery

'operating V: 11.6-14.4

BulkCharge: 14.4v

FloatCharge 13.7

 

Ctek on picture: Now that seems to be a perfect fit other than the desulf which it goes past in less than a second... What am I missing? As long as you stay away from the recon program should be fine?

Edited February 17, 20233 yr by JTK

I would also think that the internal BMS would cut off if things are wonky, but honestly I would not be brave enough to try it on a battery worth 10k

just looked at this (https://www.bluenova.co.za/wp-content/uploads/2022/05/BN13V-8-104Wh.pdf), seems like over voltage cutout is 15.6v, so it may not work when the desult kicks in, even if it's just for a second

I hooked it up... voltage on battery was 13.2v. Have voltmeter attached and voltage is steadily climbing...  13.5 now... Seems to be happy...

 

edit.. sorry not 108ah  104 wh.. dunno how I typed so stupidly

Edited February 17, 20233 yr by JTK

Nothing wrong with your way of charging while it is managed. Perhaps not for those that want to charge when no LS while eating out or at the movies. 

These Nova's are designed/sold as SLA drop-in replacements for items such as gate motors and alarms.  I agree with Scorp007, if you keep watch and switch off during float charge cycle then no problem.

We need an enterprising youngster to take a cheap but "intelligent" lead-acid charger, backtrace the main circuit IO lines, then dispose of the embedded firmware and write new firmware for a proper LiFoPO4 charging algorithm.  The hardware should be 100% compatible with both battery technologies. 

9 hours ago, Modina said:

These Nova's are designed/sold as SLA drop-in replacements for items such as gate motors and alarms.  I agree with Scorp007, if you keep watch and switch off during float charge cycle then no problem.

We need an enterprising youngster to take a cheap but "intelligent" lead-acid charger, backtrace the main circuit IO lines, then dispose of the embedded firmware and write new firmware for a proper LiFoPO4 charging algorithm.  The hardware should be 100% compatible with both battery technologies. 

May I ask why would you disconnect on float charge? 13.7v float on charger and bluenova says it wants 13.7v on float? seems match made in heaven. My limited knowledge cant find any issue other than desulf which I checked now. It pretty much skips. Does not spend any notable milliseconds on the desulf

Firstly long term float charging is not advisable on LiFePO4.  However, seeing that these Nova's are SLA drop-in replacements I guess that means that their internal controller has a way of dealing with the issue.

What I actually meant with my comment was to disable charging BEFORE the charger ***ends*** float-charging and (possibly) enters Desulf handling.  Just because you cannot see any behaviour that looks like a Desulf algorithm doesn't mean that your charger might not attempt such a state under other conditions linked to time, temperature, length of non-interrupted battery connection, etc.

Sorry Desulf is at startup only.  Not end of charge.  But pulse charging should be avoided as well.  I am no battery expert, but what is interesting is that if you put LiFePO4 in storage, the recommendation is to do so at approx 50% charge, not fully charged.

On 2023/02/18 at 10:10 AM, Modina said:

Sorry Desulf is at startup only.  Not end of charge.  But pulse charging should be avoided as well.  I am no battery expert, but what is interesting is that if you put LiFePO4 in storage, the recommendation is to do so at approx 50% charge, not fully charged.

Was aware of this for LiPo. did not know it was for LiFe also?

 

as in a Mobile you receive is half battery.. that is not a mistake. it actually gets charged to 50% before shipping..