Charging LiFePo batteries

[pmrid]

Just a question about the proper way to charge these batteries. I just bought one from Dick Smiths. The accompanying blurb says CC/CV method - constant current/voltage I suppose. All my chargers are the 3-stage type with different voltage for each stage so I am wondering whether these are OK to use. Also, I have portable solar panels for outdoor use and these have built-in controllers. I suppose both voltage and current would fluctuate with these over the course of a few hours. Are they OK to use?

[h0ughy]

I went to jaycar and bought a specific charger, not going to risk using a existing leadacid charger

[gregmc]

You don’t use staged charges on LiFePO4 batteries. Same for solar chargers. You need chargers designed for these batteries. .

[pmrid]

Those response are what initially concerned me. However, the bulk of the info I have been able to gather suggests it may not be right. The better view seems to be that much depends on the charging voltage which, for LiFePo4 batteries, needs to be in the range 14.4 to 14.6. A lot of the older PWM type devices don’t come up to that level but most MPPT chargers do.

[AdamJL]

I've got this one
https://www.jaycar.com.au/6-12vdc-1-5a-8-step-intelligent-lead-acid-and-lithium-battery-charger/p/MB3900

Just switch to "lithium mode". I don't think it's in the 14.4 - 14.6 range.

[pmrid]

It’s description says its Lithium charging voltage IS 14.5 VDC.

[Zuts]

I have had one of these for 3 years, does 6,12 volt lead acid and 12 volt lithium/LIPO. It's waterproof and has been great so far. Just a bit expensive.

https://www.automotiveelectricsonline.com.a u/noco-genius-g3500-6v-12v-3.5a-smart-battery-charge?gclid=CjwKCAiAjoeRBhAJEiwAYY 3nDK1ZkV8f06_Il4F1uRqLbvXFGzn7c2Fea 0_8RTQEdgHyjpoT32AGVRoCXI0QAvD_BwE

[AdamJL]

ha, well there you go :)

[mldee]

Hi Peter,
If it's of any help. My off-grid house LiFePO4 cells 8S3P use an MPPT solar charger (MppSolar PCM60X) set to 28.52 volts, which is where the BMS bypass shunts cut in. Been using them for a couple of years now and they're still in perfect shape. Also got two more 12V cells (with built in BMS) in parallel in the obs set to the same and still good too.

I'd stick around 14.1 or .2 for charging as these cells don't care about undercharge like lead acids.

The 14.5 you mention may be for Lithium Ion cells which have a higher terminal voltage.

[pmrid]

Thanks everyone. I have probably been led down the garden path a bit by the battery manufacturer’s specifications. And too much YouTube wisdom!