They are a great options but it is about ~80$, plus the speciality shipping( cause it’s a battery) and ~2 week turn around. Great if you want to be more environmentally friendly.( since they are actually re-celling the battery instead of replacing)
EB-1 wrote:
More importantly there are FR/HR vs. the regular drain batteries. The Fast Rate or High Rate batteries are designed for high current applications like UPS that may be >5C. If your device is drawing many C under load then FR/HR is better for performance and longevity. I don't know the details of the particular strobe and what current it draws during recycle so it may or may not matter very much, but should be considered. There are also 12V/14Ah Duracell (captive brand for Batteries+), but I don't recommend them for any but lower power applications and even so the slight improvement is not worth it.
This was somewhat relevant to my Quadra SLA to lithium conversion I posted earlier. I bought whatever was available in a similarly sized box as the original SLA and those worked fine in my older Quadra units. I also bought one 'deep cycle' lithium battery that apparently was intended as a motorcycle starter battery, because the supplier thought that one would better handle the sudden load after each strobe pop. And that seemed to be the case for my ELB400, which did not like the regular lithium batteries when doing quick, higher power bursts. (But that battery was too big to fit inside the Elinchrom box to attach to the strobe, so I didn't end up using it.)
rscheffler wrote:
But you'd have to figure out appropriate charging since it's not recommended to use the SLA charger for lithium batteries.
It's not quite that bad. According to battery manufacturer Power Sonic, you can use an ordinary SLA charger on a LiFePO4 battery with the caveat that floating charge is not supported, so you have to disconnect the charger. I do that anyway because of past experience with SLA batteries overheating when the sensor fails to detect the cut-off voltage. The SLA charger will also charge the Li battery at the slower SLA rate but no big deal. Quote from their charging FAQ:
<< The full charge open-circuit voltage (OCV) of a 12V SLA battery is nominally 13.1 and the full charge OCV of a 12V lithium battery is around 13.6. A battery will only sustain damage if the charging voltage applied is significantly higher than the full charge voltage of the battery.
This means an SLA battery should be kept below 14.7V for Stage 2 charging and below 15V for lithium. Float charging is only required for an SLA battery, recommended around 13.8V. Based on this, a charge voltage range between 13.8V and 14.7V is sufficient to charge any battery without causing damage. When selecting a charger for either chemistry, it is important to chose one that will stay between the limits listed above.
Chargers are selected to match the capacity of the battery to be charged, since the current used during charging is based on the capacity rating of the battery. A lithium battery can be charged as fast as 1C, whereas a lead acid battery should be kept below 0.3C. This means a 10AH lithium battery can typically be charged at 10A while a 10AH lead acid battery can be charged at 3A.
The charge cut-off current is 5% of the capacity, so the cutoff for both batteries would be 0.5A. Typically, the terminal current setting is determined by the charger.
Universal chargers will typically have a function to select the chemistry. This function chooses the optimal voltage charging range, and determines when the battery is fully charged. If it is charging a lithium battery, the charger should shut off automatically. If it is charging an SLA battery, it should switch to a float charge. >>
I opened my Pro-7b battery cassette today and confirmed the wiring is soldered to the FASTON F2 tabs of the battery. That's completely retarded! I'm about to replace the battery which is exhausted and will probably attach F2 connectors to the wiring. As for LiFePO4, I'm about 50-50 versus SLA only because the advantages (like weight and capacity) are not that important to me. SLA is just so cheap.
Thanks for that. SLA is dirt cheap with a long track record, but LiFePO4 is not that much more over the useful life of the battery. It will give you way more 'pops per charge' considering you can use practically 100% of the battery's capacity, whereas SLA is effectively only about 50% per charge. And LiFePO4 is supposedly ~10 year lifespan. You could put a similar Ah battery in and probably double total output, or put an even smaller one in and reduce weight even further, if that mattered.
For me with the Elinchrom Quadra, it was roughly 100-150 pops at higher output with SLA. For longer events I had to either plug in the charger to a wall outlet (which the Quadra supports while operating), or plug the charger into a Paul C Buff Vagabond Mini lithium battery & inverter. Which was kind of silly to have to run the SLA from another battery. After the LiFePO4 conversion I have rarely ever used a battery until it dropped enough for the unit to shut off. At least for me, SLA was equivalent to EV range anxiety. It never felt like it would be enough for a longer shoot. LiFePO4 eliminated that range anxiety.
@rscheffler The batteries for my AcuteB and Pro-B2 packs are exhausted. The Pro-B2 needs a soldering iron, or I have to clip the leads, while I have serviced the AcuteB myself in the past and the leads are simple FASTON F2. Therefore, I decided to refresh my AcuteB first. My SLA boat anchor of choice (Power-Sonic PSH-1255F2-FR) is out of stock on eBay and Amazon, so I decided to research the LiFePO4 (LFP) situation. Basically, they are all made in China and the brand variety is immense. An LFP for AcuteB is $25-40 with some variation in spec. The Profoto packs want high-drain. I heard from users that ordinary-drain units (5A) will fail to charge the caps, although I don't fully buy that story. I nonetheless ordered a 10A version for $30 and will test it tomorrow.
This modern generation of LFP battery has BMS (battery management system). This prevents overdraw, overdischarge, and overcharge—possibly overheating, too. Because BMS prevents overcharging, LFP can drop into any appliance or circuit designed for SLA and the trickle-charge phase has no adverse effect. Amazon buyers are dropping LFP into vehicles, solar power storage, RVs, UPS, ham radio, etc.
My foray into LFP is a bust for several reasons. Firstly, the battery for my AcuteB arrived DOA meaning it would not accept a charge from the included wallwart or from my two Profoto branded ones. Secondly, the residual charge was at a voltage that upset the electronics of the pack, which beeped strangely and lit all the charge LEDs (not normal behavior). Thirdly, I now recall that the state-of-charge cannot be properly acertained by the AcuteB when LFP is used: I consider this a quality-of-life annoyance. Fourthly, the claimed amperage is quite meager. Finally, I have further reason to consider this battery tech unreliable based on user reviews on Amazon of several brands (all Chinese) and it comes down to BMS design, build quality and testing. One Amazon customer even described his teardown and rework of a faulty BMS circuit board. There are no reputable manufacturers in this space. I will come back to my AcuteB project later with good ol' SLA.
Meanwhile, the Pro-B2 battery replacement is underway. I have acquired all the needed components: crimper, wire cutter, 10-gauge stranded, FASTON F2 receivers, butt-splice connectors, and a big-ass Power-Sonic SLA battery. I thought about resoldering the connection as was done by Profoto but cannot stomach the stupidity. Their implementation makes battery replacement unattractive, and was perhaps deliberate so as to encourage customers to buy a whole new cassette. The hot F2 tab has three soldered wires leading to the fuses. I intend to cut those leads and crimp them together with a single F2 connector for the new battery. The return lead, also soldered, is a single wire that will get the same treatment. For battery, I ordered the PS-12120F2 off Amazon and it should serve perfectly. The rated transient draw is a whopping 180A (2kW) for 5sec. The Pro-B2 should be overjoyed with that inrush spec given that each lead is fused at 40A.
You are doing it right. It's really not good practice to solder F2 connectors on the battery, but if necessary use something like a D550 or D650 to get it done fast.
Hopefully you can find some decent FASTON F2 crimp-ons. Some of them are really flimsy these days and between the weak crimp part and flimsy slide-on part it is doubtful for 30A+. I just happened to run into that issue with some 10 gauge and UPS battery setup. Fortunately I had few older ones.
@EB-1 Thanks, the Weller models look suitable if it comes to that. Giant bricks of Pb make fearsome heatsinks. I still aim to connect everything by crimping, and have all the parts and tools on my dining room table for a weekend project. From further online research, I learned that the Pro-7b has a Fast Recharge Mode of 2.8sec. My pack, however, is the successor Pro-B2, and it recharges in 1.8sec! That means a draw of 56A, not including surge. The entire Internet says F2 is good for 20A max, so that's a bit scary. I also need a pair of 10-gauge leads on the hot tab to avoid overheating. I'll see if this Supco F2 receiver (US-made) can handle the demand.
Anyone needing a fresh battery in this Profoto cassette should strongly consider having it done professionally unless you have a knack for electrical hacking and own a complete toolset. I only continue out of a grim sense of commitment.
The Supco F2s are generally OK, certainly better than some flimsies.
I have not done the math for your flash, but larger SOHO UPS are rated over 940W at 120VAC output so about 8A. At 100% efficiency that would take 40A at 24VDC. Mainstream manufacturers build UPS that way in high volume, so there must be some margin of safety. Maybe you can fire off a reasonable number of pops and then feel the connections to see if there is any significant heat. In practical use they won't be continuous. I would not make or break the F2 connections under high load however. I use the Anderson SB50 connectors for hot plugging of batteries at higher loads, up to 50A.
@EB-1 Yeah, I was curious how APC was powering their intermediate-sized UPS products. Those battery sets (e.g. RBC6) are using two 12V SLA with F2 but the series connection allows 24V for double the power without doubling the current draw off the F2 tabs. As for Powerpole, I scoured the Anderson web site for a solution like a direct F2-to-SB50 adapter: no luck.
rico wrote:
My foray into LFP is a bust for several reasons. Firstly, the battery for my AcuteB arrived DOA meaning it would not accept a charge from the included wallwart or from my two Profoto branded ones. Secondly, the residual charge was at a voltage that upset the electronics of the pack, which beeped strangely and lit all the charge LEDs (not normal behavior). Thirdly, I now recall that the state-of-charge cannot be properly acertained by the AcuteB when LFP is used: I consider this a quality-of-life annoyance. Fourthly, the claimed amperage is quite meager. Finally, I have further reason to consider this battery tech unreliable based on user reviews on Amazon of several brands (all Chinese) and it comes down to BMS design, build quality and testing. One Amazon customer even described his teardown and rework of a faulty BMS circuit board. There are no reputable manufacturers in this space. I will come back to my AcuteB project later with good ol' SLA.
Meanwhile, the Pro-B2 battery replacement is underway. I have acquired all the needed components: crimper, wire cutter, 10-gauge stranded, FASTON F2 receivers, butt-splice connectors, and a big-ass Power-Sonic SLA battery. I thought about resoldering the connection as was done by Profoto but cannot stomach the stupidity. Their implementation makes battery replacement unattractive, and was perhaps deliberate so as to encourage customers to buy a whole new cassette. The hot F2 tab has three soldered wires leading to the fuses. I intend to cut those leads and crimp them together with a single F2 connector for the new battery. The return lead, also soldered, is a single wire that will get the same treatment. For battery, I ordered the PS-12120F2 off Amazon and it should serve perfectly. The rated transient draw is a whopping 180A (2kW) for 5sec. The Pro-B2 should be overjoyed with that inrush spec given that each lead is fused at 40A....Show more →
Sorry to read it didn't work out with LFP. I guess I got lucky with my Quadra conversion.
rico wrote:
@EB-1@ Yeah, I was curious how APC was powering their intermediate-sized UPS products. Those battery sets (e.g. RBC6) are using two 12V SLA with F2 but the series connection allows 24V for double the power without doubling the current draw off the F2 tabs. As for Powerpole, I scoured the Anderson web site for a solution like a direct F2-to-SB50 adapter: no luck.
It's trivial to make you own cables if you have basic tools. The simplest is to buy a SB-50 cable to 10 gauge wires and crimp on Supco T1114 or T1112 or similar F2 FASTONs.
The consumer and SOHO UPS are mostly using F2 (some asymmetrical F1/F2 historically). The enterprise UPS like the APC 1500 sinewave series that are about $600-700 new use two 12V 18Ah batteries (RBC7 pack) rather than the two 12V 8-9Ah batteries in their basic 1500VA UPS and some that use the wider 11-12Ah batteries. The 12V 18Ah batteries use nut and bolt connectors on the batteries and the UPS are equipped with SB50 connectors natively for fast swaps and reliable connections. Those UPS are over 52 lbs. with half the weight in the batteries.
I still aim to connect everything by crimping, and have all the parts and tools on my dining room table for a weekend project. From further online research, I learned that the Pro-7b has a Fast Recharge Mode of 2.8sec. My pack, however, is the successor Pro-B2, and it recharges in 1.8sec! That means a draw of 56A, not including surge. The entire Internet says F2 is good for 20A max, so that's a bit scary. I also need a pair of 10-gauge leads on the hot tab to avoid overheating. I'll see if this Supco F2 receiver (US-made) can handle the demand.