Panasonic HHR-3MPA NiMH 2050 mAh cells

I thought I'd start a new thread about these cells, as they are interesting. They came with the Panasonic DMW-LZACKIT Accessory Kit for Panasonic digital cameras along with the BQ-321 charger. This was intended for Panasonic cameras LZ2, LZ3 and LZ5 that took AA batteries in the days (2005/2006) before cameras all went lithium ion (Boo!!!). These days the kit is a clearance item, but the BQ-321 is still a nice charger (see other thread).

What's interesting about these cells? Well, firstly, my samples have a date code of 06-08 (August 2006), making them 4 1/2 years old, and here is how they performed out of the shrink wrap:

Initial voltages: 1.267 1.268 1.265 1.267 V
Intial charge: 1152 1097 1054 1075 mAh (discharged at 200 mA on the C9000)

Do you have the thought that Panasonic were selling low self-discharge cells in disguise before Sanyo laid claim to the idea? (These cells are not labelled as pre-charged and ready to use.)

Another interesting thing about these cells is they do not have the characteristic high voltage on full charge that Eneloops do. If you charge them on the C9000 they terminate on minus delta V and never reach 1.47 V. They do however terminate nicely and at the expected time. Here is the result of charging from empty at 1000 mA:

Time: 140 / 147 / 144 / 146 minutes
Charge supplied: 2114 / 2211 / 2177 / 2200 mAh

A preliminary discharge test after charging for approximately 2300 mAh at 200 mA gave:

Discharge: 1895 / 1875 / 1811 / 1794 mAh

This is a little low for the 2050 rating, but I think they might perk up a bit with a few more cycles. After all, they have been sleeping for nearly five years...

I will continue to play with them a bit and see if I can get the capacity nearer to 2000 mAh.

I don't have the patience to run a full break-in cycle on these cells, but another cycle has the capacity readings up to:

1915 / 1904 / 1863 / 1877 mAh

It looks like the first two are working a little better than the second two. Not quite up to the marked 2050 mAh, but perhaps age has had an effect on them.

According to Panasonic Canada website, these HHR-3MPA should last 1000 cycles and have a 80% charge retention after 1 years.

Pansonic also have the HHR-3MR with 1200 cycles and the latest HHR-3MV with 1600 cycles.

Performance is quite good for battery manufactured in 2006. Most of my cells capacity is around 1900 mAh. Internal impedance measured with a HP 4328A Milliohmmeter (1 kHz AC) is between 32-42 mΩ. This is a higher than eneloop which measured between 20-25 mΩ.

I am currently re-testing all the cells including 2 that just came out of the package.
Will post more info once testing is done.

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Result from Discharge on C9000 at 400 mA, Impedance measured at end of discharge.
All cells have a date code of 06-08 (August 2006)

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These four have 23 cycles (Discharge at 300 mA in lights, fast charge weekly at 1.15A in K6000)

Cell 1 1896 mAh / 32 mΩ
Cell 2 1903 mAh / 34 mΩ
Cell 3 1932 mAh / 32 mΩ
Cell 4 1948 mAh / 31 mΩ

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These two have about 9 cycles (Discharge at 300 mA in lights, charge at 550 mA in BQ-321)

Cell 5 1919 mAh / 31 mΩ
Cell 6 1956 mAh / 29 mΩ (first cell to go past 1950 mAh

10th cycle: Charged with BQ-321

Cell 5 1927 mAh / 32 mΩ
Cell 6 1923 mAh / 30 mΩ

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Here is the initial discharge result for the 2 new one just came out of plastic:

Cell 7 878 mAh / 35 mΩ
Cell 8 1141 mAh / 32 mΩ

1st cycle: Charged with BQ-321

Cell 7 1788 mAh / 31 mΩ
Cell 8 1728 mAh / 30 mΩ

2nd cycle: Charged with BQ-321

Cell 7 1855 mAh / 27 mΩ
Cell 8 1841 mAh / 27 mΩ

3rd cycle: Refresh and Analyze with C9000 at 400 mA Charge and Discharge

Cell 7 1864 mAh / 33 mΩ
Cell 8 1836 mAh / 32 mΩ

Mr Happy said:

This was intended for Panasonic cameras LZ2, LZ3 and LZ5 that took AA batteries in the days (2005/2006) before cameras all went lithium ion (Boo!!!).

Click to expand...

For point and shoots I buy Fuji which still take two AA batteries.

Just got 2 of the Panasonic DMW-LZACKIT Accessory Kits for a total of under $14 delivered for both (had stickers of $29.95 on each box) after reading the thread referenced in OP. I wanted chargers for my duaghters and these looked like the easiest decent chargers and you can't beat the price. Just finished an initial discharge at 500mA on the batteries also dated 0608 (Aug 2006) on my C9000 and got 991, 1173, 1151, and 1121 mAh. Next is a breakin.

After first break-in (charge @ 200mA and discharge at 400mA) the cells had: 2004, 1916, 1987, and 1967 mAh respectively. Not bad for 5 year old batteries that have never been used.

My 2pcs arrived at 1.27V. Shows 773/1065mAh 400mA in Maha.
Break-In 1849/1843 90% from declared 2050

Ri based on Maha data
VDC V2 Ri
1.67 1.41 0.086
1.66 1.41 0.081