Powersonic "Smart Battery" tested

On Wednesday, September 9, 2020 at 7:37:17 PM UTC-4, wrote:
I wonder how much of a current draw the bluetooth feature is.

Probably very little. If you turn on Bluetooth in your phone, do you notice much of a reduction in the battery life? And this is a much larger battery.

But yeah the only advantage of having this feature, to my mind, is the (potential) ability to monitor the individual cells within the battery. Other than that, I use a charger that tells me how much charge (amp-hours) go into the battery, and it should correspond to how long I used it in the glider.. And my current 12 amp-hour LiFePO4 battery has so much capacity relative to my avionics' needs that even if I forgot to charge it since the last flight it would still easily last for the current flight. Your situation may differ, especially if you have a transponder.

The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

On Thursday, September 10, 2020 at 12:48:52 AM UTC-4, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

Some months ago I bought several "PowerSync" (related to "PowerSonic"?) LFP batteries, the non-smart version (no Bluetooth), for about $32 each, from a US seller on ebay. Rated 7.5 AH, and the same standard "brick" size as the common 7AH SLA batteries. At that price, they are cheaper than SLAs (since they will last at least twice as many years). I cut one open, so I can tell you that (1) the ones sold at that price were 2 years old when sold (date stamped late 2017), not great but no big deal, (2) the cells are the small 18650 size, like the ones used in laptop batteries (but LFP chemistry in this case), and (3) yes it includes a full BMS including cell balancing. I've used them in an electric bicycle and in an electric mower, so I can report they work OK in high-drain use (but the BMS shuts off at about 20 amps). In the glider I prefer the larger 12AH battery, but one of these smaller 7.5AH ones is my standard backup plan.

Note that a "7AH" SLA battery that is 2-3 years old will only give you about 3 AH or so if you don't want to damage it by fully discharging it, and the voltage will be pretty low by then. Tested one of these 7.5 AH LFPs by discharging 6 AH out of it, voltage was still well over 13V. The spec sheet claims they are "designed to work with AGM chargers", so you don't even need a new charger if you switch to them from SLAs, although something like the Imax B6 is better.

On Thursday, September 10, 2020 at 6:55:22 AM UTC-7, wrote:
On Thursday, September 10, 2020 at 12:48:52 AM UTC-4, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!
Some months ago I bought several "PowerSync" (related to "PowerSonic"?) LFP batteries, the non-smart version (no Bluetooth), for about $32 each, from a US seller on ebay. Rated 7.5 AH, and the same standard "brick" size as the common 7AH SLA batteries. At that price, they are cheaper than SLAs (since they will last at least twice as many years). I cut one open, so I can tell you that (1) the ones sold at that price were 2 years old when sold (date stamped late 2017), not great but no big deal, (2) the cells are the small 18650 size, like the ones used in laptop batteries (but LFP chemistry in this case), and (3) yes it includes a full BMS including cell balancing. I've used them in an electric bicycle and in an electric mower, so I can report they work OK in high-drain use (but the BMS shuts off at about 20 amps). In the glider I prefer the larger 12AH battery, but one of these smaller 7.5AH ones is my standard backup plan.

Note that a "7AH" SLA battery that is 2-3 years old will only give you about 3 AH or so if you don't want to damage it by fully discharging it, and the voltage will be pretty low by then. Tested one of these 7.5 AH LFPs by discharging 6 AH out of it, voltage was still well over 13V. The spec sheet claims they are "designed to work with AGM chargers", so you don't even need a new charger if you switch to them from SLAs, although something like the Imax B6 is better.

Powersonic is unrelated to "Powersync" whoever that is. Powersonic is a Japanese company that has been making batteries for decades.

A higher quality charger is the Victron Smart Blue 12V/5A. Will charge any chemistry and is highly configurable through the Victron Connect app. More expensive though.

On Thursday, September 10, 2020 at 11:53:38 AM UTC-4, jfitch wrote:
Powersonic is unrelated to "Powersync" whoever that is. Powersonic is a Japanese company that has been making batteries for decades.

Are you confusing them with Panasonic? Powersonic is an American company.

https://www.power-sonic.com/about/

On 9/10/20 7:55 AM, wrote:
On Thursday, September 10, 2020 at 12:48:52 AM UTC-4, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

Some months ago I bought several "PowerSync" (related to "PowerSonic"?) LFP batteries, the non-smart version (no Bluetooth), for about $32 each, from a US seller on ebay. Rated 7.5 AH, and the same standard "brick" size as the common 7AH SLA batteries. At that price, they are cheaper than SLAs (since they will last at least twice as many years). I cut one open, so I can tell you that (1) the ones sold at that price were 2 years old when sold (date stamped late 2017), not great but no big deal, (2) the cells are the small 18650 size, like the ones used in laptop batteries (but LFP chemistry in this case), and (3) yes it includes a full BMS including cell balancing. I've used them in an electric bicycle and in an electric mower, so I can report they work OK in high-drain use (but the BMS shuts off at about 20 amps). In the glider I prefer the larger 12AH battery, but one of these smaller 7.5AH ones is my standard backup plan.

Note that a "7AH" SLA battery that is 2-3 years old will only give you about 3 AH or so if you don't want to damage it by fully discharging it, and the voltage will be pretty low by then. Tested one of these 7.5 AH LFPs by discharging 6 AH out of it, voltage was still well over 13V. The spec sheet claims they are "designed to work with AGM chargers", so you don't even need a new charger if you switch to them from SLAs, although something like the Imax B6 is better.


Three things wrong with the claim that these are LFP batteries. You
said voltage was well over 13 volts after almost a full discharge, but
real LFP's are 12.8 nominal, with four cells. 12.5 volts near the end
of a discharge cycle would be a lot more believable.

The fact that the cells are 18650 form factor should be a tipoff in itself.

Most importantly, LFP doesn't have the energy density needed to pack
that much power into four small cells.

So what you have is some Li-ion battery mis-branded as being LFP.

-Dave

On Thursday, September 10, 2020 at 4:04:57 PM UTC-4, kinsell wrote:
On 9/10/20 7:55 AM, wrote:
On Thursday, September 10, 2020 at 12:48:52 AM UTC-4, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

Some months ago I bought several "PowerSync" (related to "PowerSonic"?) LFP batteries, the non-smart version (no Bluetooth), for about $32 each, from a US seller on ebay. Rated 7.5 AH, and the same standard "brick" size as the common 7AH SLA batteries. At that price, they are cheaper than SLAs (since they will last at least twice as many years). I cut one open, so I can tell you that (1) the ones sold at that price were 2 years old when sold (date stamped late 2017), not great but no big deal, (2) the cells are the small 18650 size, like the ones used in laptop batteries (but LFP chemistry in this case), and (3) yes it includes a full BMS including cell balancing. I've used them in an electric bicycle and in an electric mower, so I can report they work OK in high-drain use (but the BMS shuts off at about 20 amps). In the glider I prefer the larger 12AH battery, but one of these smaller 7.5AH ones is my standard backup plan.

Note that a "7AH" SLA battery that is 2-3 years old will only give you about 3 AH or so if you don't want to damage it by fully discharging it, and the voltage will be pretty low by then. Tested one of these 7.5 AH LFPs by discharging 6 AH out of it, voltage was still well over 13V. The spec sheet claims they are "designed to work with AGM chargers", so you don't even need a new charger if you switch to them from SLAs, although something like the Imax B6 is better.


Three things wrong with the claim that these are LFP batteries. You
said voltage was well over 13 volts after almost a full discharge, but
real LFP's are 12.8 nominal, with four cells. 12.5 volts near the end
of a discharge cycle would be a lot more believable.

The fact that the cells are 18650 form factor should be a tipoff in itself.

Most importantly, LFP doesn't have the energy density needed to pack
that much power into four small cells.

So what you have is some Li-ion battery mis-branded as being LFP.

-Dave

Not at all. The thing is packed with 20 of these cells (4S 5P configuration), 1500 mAH per 18650 cell is reasonable. LFP is famous for holding the voltage above 13V (for a 4-cell battery) until it's almost empty. I didn't discharge it all the way, only 6AH out of the nameplate 7.5AH. (I didn't care enough about the exact capacity to risk stressing the battery with a full discahrge.) If these cells were really Li-ion then 4S would be around 14.4V nominal and much higher than that when charging. Instead it runs around 13.4-13.6V for most of the charging, as it should for LFP.

I have photos of the innards of this thing if anybody's interested.

And no I'm not affiliated with the seller... In fact I put off buying them for a long time since I didn't like the seller's flippant responses to my technical questions, but eventually I found some info elsewhere online, took the risk, and am happy with what I got.

Again, these have nothing to do with the batteries in the subject line, which are LFP, well documented, from a long time reputable supplier. If you want to have a discussion of some No-Name brand ebay special, I suggest you start a separate thread on them.

On Thursday, September 10, 2020 at 1:34:40 PM UTC-7, wrote:
On Thursday, September 10, 2020 at 4:04:57 PM UTC-4, kinsell wrote:
On 9/10/20 7:55 AM, wrote:
On Thursday, September 10, 2020 at 12:48:52 AM UTC-4, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

Some months ago I bought several "PowerSync" (related to "PowerSonic"?) LFP batteries, the non-smart version (no Bluetooth), for about $32 each, from a US seller on ebay. Rated 7.5 AH, and the same standard "brick" size as the common 7AH SLA batteries. At that price, they are cheaper than SLAs (since they will last at least twice as many years). I cut one open, so I can tell you that (1) the ones sold at that price were 2 years old when sold (date stamped late 2017), not great but no big deal, (2) the cells are the small 18650 size, like the ones used in laptop batteries (but LFP chemistry in this case), and (3) yes it includes a full BMS including cell balancing. I've used them in an electric bicycle and in an electric mower, so I can report they work OK in high-drain use (but the BMS shuts off at about 20 amps). In the glider I prefer the larger 12AH battery, but one of these smaller 7.5AH ones is my standard backup plan.

Note that a "7AH" SLA battery that is 2-3 years old will only give you about 3 AH or so if you don't want to damage it by fully discharging it, and the voltage will be pretty low by then. Tested one of these 7.5 AH LFPs by discharging 6 AH out of it, voltage was still well over 13V. The spec sheet claims they are "designed to work with AGM chargers", so you don't even need a new charger if you switch to them from SLAs, although something like the Imax B6 is better.


Three things wrong with the claim that these are LFP batteries. You
said voltage was well over 13 volts after almost a full discharge, but
real LFP's are 12.8 nominal, with four cells. 12.5 volts near the end
of a discharge cycle would be a lot more believable.

The fact that the cells are 18650 form factor should be a tipoff in itself.

Most importantly, LFP doesn't have the energy density needed to pack
that much power into four small cells.

So what you have is some Li-ion battery mis-branded as being LFP.

-Dave
Not at all. The thing is packed with 20 of these cells (4S 5P configuration), 1500 mAH per 18650 cell is reasonable. LFP is famous for holding the voltage above 13V (for a 4-cell battery) until it's almost empty. I didn't discharge it all the way, only 6AH out of the nameplate 7.5AH. (I didn't care enough about the exact capacity to risk stressing the battery with a full discahrge.) If these cells were really Li-ion then 4S would be around 14.4V nominal and much higher than that when charging. Instead it runs around 13.4-13.6V for most of the charging, as it should for LFP.

I have photos of the innards of this thing if anybody's interested.

And no I'm not affiliated with the seller... In fact I put off buying them for a long time since I didn't like the seller's flippant responses to my technical questions, but eventually I found some info elsewhere online, took the risk, and am happy with what I got.

On Thursday, September 10, 2020 at 3:02:28 PM UTC-7, jfitch wrote:
Again, these have nothing to do with the batteries in the subject line, which are LFP, well documented, from a long time reputable supplier. If you want to have a discussion of some No-Name brand ebay special, I suggest you start a separate thread on them.

On Thursday, September 10, 2020 at 1:34:40 PM UTC-7, wrote:
On Thursday, September 10, 2020 at 4:04:57 PM UTC-4, kinsell wrote:
On 9/10/20 7:55 AM, wrote:
On Thursday, September 10, 2020 at 12:48:52 AM UTC-4, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

Some months ago I bought several "PowerSync" (related to "PowerSonic"?) LFP batteries, the non-smart version (no Bluetooth), for about $32 each, from a US seller on ebay. Rated 7.5 AH, and the same standard "brick" size as the common 7AH SLA batteries. At that price, they are cheaper than SLAs (since they will last at least twice as many years). I cut one open, so I can tell you that (1) the ones sold at that price were 2 years old when sold (date stamped late 2017), not great but no big deal, (2) the cells are the small 18650 size, like the ones used in laptop batteries (but LFP chemistry in this case), and (3) yes it includes a full BMS including cell balancing. I've used them in an electric bicycle and in an electric mower, so I can report they work OK in high-drain use (but the BMS shuts off at about 20 amps). In the glider I prefer the larger 12AH battery, but one of these smaller 7.5AH ones is my standard backup plan.

Note that a "7AH" SLA battery that is 2-3 years old will only give you about 3 AH or so if you don't want to damage it by fully discharging it, and the voltage will be pretty low by then. Tested one of these 7.5 AH LFPs by discharging 6 AH out of it, voltage was still well over 13V. The spec sheet claims they are "designed to work with AGM chargers", so you don't even need a new charger if you switch to them from SLAs, although something like the Imax B6 is better.


Three things wrong with the claim that these are LFP batteries. You
said voltage was well over 13 volts after almost a full discharge, but
real LFP's are 12.8 nominal, with four cells. 12.5 volts near the end
of a discharge cycle would be a lot more believable.

The fact that the cells are 18650 form factor should be a tipoff in itself.

Most importantly, LFP doesn't have the energy density needed to pack
that much power into four small cells.

So what you have is some Li-ion battery mis-branded as being LFP.

-Dave
Not at all. The thing is packed with 20 of these cells (4S 5P configuration), 1500 mAH per 18650 cell is reasonable. LFP is famous for holding the voltage above 13V (for a 4-cell battery) until it's almost empty. I didn't discharge it all the way, only 6AH out of the nameplate 7.5AH. (I didn't care enough about the exact capacity to risk stressing the battery with a full discahrge.) If these cells were really Li-ion then 4S would be around 14..4V nominal and much higher than that when charging. Instead it runs around 13.4-13.6V for most of the charging, as it should for LFP.

I have photos of the innards of this thing if anybody's interested.

And no I'm not affiliated with the seller... In fact I put off buying them for a long time since I didn't like the seller's flippant responses to my technical questions, but eventually I found some info elsewhere online, took the risk, and am happy with what I got.

I concur. I think this is the moshe? is referring to:
https://tinyurl.com/yy22xxvc
It does not have a datasheet, so I don't know how moshe can assert there is a BMS. For sure, Powersync has nothing to do with PowerSonic. More likely, the name was chosen to confuse buyers into jumping to that conclusion. There are reputable LFP battery manufacturers out there, so there is no good reason to buy this.

Tom

On Wednesday, September 9, 2020 at 9:48:52 PM UTC-7, wrote:
The bluetooth feature is a gimmick. What really makes these attractive is that they are about 1/2 the price of equivalent the K2 battery!

Not sure why anyone would pay $150 for a K2 Battery.

Richard