Battle Born Charging
This might answer some recent questions. The table is not accurate wrt to the BB comments--don't go by it by the table itself. Wade through the questions and answers to get the true picture. Tak...
Forum Discussion
I am currently in possession of one such 100 amp Powermax adjustable voltage model. Originally a 75 amp model arrived with the 100 amp sticker, and somebody's favorite converter purveyor, when confronted, whome it was bought through, told me that 2 depleted group 31 batteries in parallel could never accept more than 75 amps and that everything was fine and just accept it and he knows what he is talking about and implying I did not.
Eventually the physically larger 100 amp model did arrive, yet we never got more than 94 amps from it. I figured it was less than 120vac input voltage, as it has to be near maxing out a 15 amp circuit.
More recently this stored powermax saw the light of day, and I put some jumper cables on it putting it on a 7.5 volt 6 month old group 94 and was only getting 75 amps from it, more than enough for the task at hand, but I took it to my workshop to investigate.
The Aluminum output studs did not sit nice and flat on the circuit board and looked like some overheating/oxidation might have occurred there. They do now. The finger twist 500 ohm potentiometer makes precise dial adjustments difficult, but appears to be a high quality Potentiometer. I am getting a 10 turn 500 ohm pot for it.
I added a 60mm fan opposite end of the provided 80Mm fan. This fan is on its own rocker switch and also controls a new illuminated voltmeter.
I'd really like a hard mounted Ammeter on it, but it is not really mine and my clampmeter is fine for now. I have two 8 awg 45 amp anderson powerpoles as outputs on it currently.
So I depleted my newish Group31 Northstar 103AH AGM to 71 amp hours from full, then turned off most loads. I hook up the 100 amp powermax, and again only get 94 amps out of it. I then hook up my Meanwell rsp-500-15 in parallel, and 134 amps still can't get my battery instantly to absorption voltage, and 3 minutes later the AC circuit breaker blew. I restarted just the powermax and the battery accepped the 94 amps for several more minutes before rising to absorption voltage, at which point amps started tapering, and they tapered surprisingly quickly.
So Being told that TWO of these 50% depleted group 31 AGMS in parallel could never accept more than 75 amps is enraging, as one of them depleted below 50% accepted over 130 amps and then 94 amps for over 10 minutes before hitting absorption voltage.
What are the max acceptable charge/discharge rates for the BMS in BB Lifepo4 batteries? Unless they can handle what my Lead acid Northstar AGM handles, I am not interested in owning one.
My only worry with my Northstar AGM is overtemperature, which means dont hi rate recharge from a well depleted state in hot ambient temps and turn off or lower voltage of charging source once amps taper to 0.5@ 14.7v.
Not having to get to truly full as often as possible seems to be the best advantage of Lifepo4, and Lifepo4 only winds up 'cheaper' if one gets the rated cycles out of it, which is not a given.
Eventually the physically larger 100 amp model did arrive, yet we never got more than 94 amps from it. I figured it was less than 120vac input voltage, as it has to be near maxing out a 15 amp circuit.
More recently this stored powermax saw the light of day, and I put some jumper cables on it putting it on a 7.5 volt 6 month old group 94 and was only getting 75 amps from it, more than enough for the task at hand, but I took it to my workshop to investigate.
The Aluminum output studs did not sit nice and flat on the circuit board and looked like some overheating/oxidation might have occurred there. They do now. The finger twist 500 ohm potentiometer makes precise dial adjustments difficult, but appears to be a high quality Potentiometer. I am getting a 10 turn 500 ohm pot for it.
I added a 60mm fan opposite end of the provided 80Mm fan. This fan is on its own rocker switch and also controls a new illuminated voltmeter.
I'd really like a hard mounted Ammeter on it, but it is not really mine and my clampmeter is fine for now. I have two 8 awg 45 amp anderson powerpoles as outputs on it currently.
So I depleted my newish Group31 Northstar 103AH AGM to 71 amp hours from full, then turned off most loads. I hook up the 100 amp powermax, and again only get 94 amps out of it. I then hook up my Meanwell rsp-500-15 in parallel, and 134 amps still can't get my battery instantly to absorption voltage, and 3 minutes later the AC circuit breaker blew. I restarted just the powermax and the battery accepped the 94 amps for several more minutes before rising to absorption voltage, at which point amps started tapering, and they tapered surprisingly quickly.
So Being told that TWO of these 50% depleted group 31 AGMS in parallel could never accept more than 75 amps is enraging, as one of them depleted below 50% accepted over 130 amps and then 94 amps for over 10 minutes before hitting absorption voltage.
What are the max acceptable charge/discharge rates for the BMS in BB Lifepo4 batteries? Unless they can handle what my Lead acid Northstar AGM handles, I am not interested in owning one.
My only worry with my Northstar AGM is overtemperature, which means dont hi rate recharge from a well depleted state in hot ambient temps and turn off or lower voltage of charging source once amps taper to 0.5@ 14.7v.
Not having to get to truly full as often as possible seems to be the best advantage of Lifepo4, and Lifepo4 only winds up 'cheaper' if one gets the rated cycles out of it, which is not a given.
