9 V rechargeable batteries from ebay - are there any good batteries?

[dragonfruit]

Are there any good, cheap 9 V rechargeable batteries from ebay?
I see there brands like Tweets, BP, GodP, POWER, GTL, BTY.

Have you ever tried these?

I had very bad experience with BTY AA batteries, but never tried 9 V ones, though.

 

[moldyoldy]

I have never purchased 9V rechargeable batteries from ebay. Why not any of the many companies that frequent CPF? or even Amazon.com? Although I do purchase button cells on eBay, I have too many better choices for the larger rechargeable batteries.

Taking a casual glance thru an eBay search for 9V rechargeable batteries, besides the brands you noted, I also see GP and Tenergy 9V cells. Those are also sold on CPF-vendor websites. However, too many products found on eBay have a dubious record for being relabled to a "good" brand. If I wanted rechargeable cells, I would rather pay a higher price for a more believable product from a credible vendor.

 

[InHisName]

I bought some NexCels from eBay back in '09.
I got 12 AAAs now are all HIGH after 60-70 cycles.
17Ma discharge 10 hours / day - 4 days. ReCharge @ 5/4/300ma

I also bought 4 9V and they are doing fine.
Only cycled them 4x each.
No c9000 data on them though.
They last a real long time on my meters.
Except for one that I forget and it does not auto shut off.
That one meter is why 4x cycles and not 2x cycles or less.
I paid about $4 with shipping each.
I was money ahead by time of 3x cycle.

 

[angoam]

I have looked for 9V batt. for multimetrs. Before, around 5 years ago, I have trying to use Tenergy Recargebles 9V and have bad experiance. Tenergy 9V NiMh (blue color), has very big self discharge rate, and need some special? charger: When I try charge them from RadioShack Universal Carger -"AA-AAA-9V" one batterey pops, due to overcharging charging current was around 100mA for 250mHh battery. Then I have charged Tenergy 9V battery by self-made charger (Power supply and resistor). But due to self discharge, I used them very rare.

Last year. I bought couple GTL 9V rechargeble battery from Ebay for 2for$5. To try. It shows 300mAh NiMh on sticker. But it is "Chineese Brand"
They came with 9.25V on terminals. I try to measure real capacity, on 100 mA discharge current, it count around 50mAh. But I'm using B6 clone, and can not to set discharge less than 100mA. It is too much for this kind of battereys...
Internal Resistance of battery was 0.5Ohm - not bad.

I not shure it is Ni-Cd/Mh inside. And wanted to open battery, to see what inside? before trow it to garbage. But, I gave them last chance. Charged FULL at 100mAh 20hours. Battereys was cold and not pops! Has 9.25V full charged. Then, I have put them into Multimetr DT9205, and Digital LCD Bath Scale.

After 6(SIX!!!) month battereys hold charge and has same 9.2V But multimeter only works around 5 minutes and then show "low batt", but after couple minutes rest can works another 5min. But I carged battery only once, 6 month ago, and using multimerer often (definetly NOT every day

Finaly I did not open/discard this batterey, and order another couple for $5 with free shipping from Ebay last month, got another "brand" -BTY : the same chineese bull....t (Clone). But seriously, it is very good choice for some kind of testers that need 9V battereys, and usually do not have hi power consumtion, and do not used frequently . Cheap and long life accu!
Very interesting, what is inside: Ni, Li, Lead .... ? Battery is very lightweight, and reccomended charge current is 17mA for 300?mAh...

 

[Yamabushi]

If I was going to buy a rechargeable 9V on eBay, the only one I would consider (based on my experience with their other sizes) is the Maha Imedion. Note that there are currently 8.4V and 9.6V versions. But they are not cheap.

 

[ChrisGarrett]

I went with 4 Tenergy Centuras and a little two bay Tenergy wall charger and they work well.

I think I paid $25 shipped from a big Ebay dealer on the West Coast and things are nifty.

Chris

 

[angoam]

Finally, I crack my 9 Volt battereys. It was not to hard to open them even without "cosmetical" damages. Exept Tenergy (blue) , but it was dead any way, and Tenergy centura (white) - I did not open, because it new, in good condition. Both Tenergy in Thermal Shrink Tube. Rest battareys MAHA, and chineese (BTY,GTL) in plastic case with stickers. Very ease open without damages!

What I see inside? Blue Tenergy 250mAh has 7 "discus"(button) Ni-Cd cells - worst! This kind of cells absolutely NOT overchaarge protected. It is older type of accumulators - ease overheating and pops! (0.2C-maximum charge current).

On picture one cell is popped, another - leaked...

Chineese are much better. Using seven cylyndrical 10x15mm probably Ni-Mh cells is uncommon shape, shorter then 10180. may be special size to fit to 9V battery.

Cells without any marking (it is normal...) GTL even has self curing (polymer) fuse LV175 (4A), but fuse is useless, because trash chinees cells can not give more than 100-200mA...

MAHA Imedion 250 mAh(low self discharge???) has 7 rectangular 5x14x22mm cells probably Ni-Mh

Conclusion:

Voltage.
All batt. has 7 Ni cells 8.4 Volts
Only MAHA Imedion marked 8.4V rest battereys 9V - Not big difference nominal/maximal voltage.

Capacity.
I have not enouh time to mesure real capacity, need very low discharge current (around 10mA) but I think all have simillar low capacity around 200 mAh (exept GTL with very low quality cells BUT WITH VERY LOW SELF DISCARGE.... strange, but real!) May be I will mesure mAh later...

Internal Resistanse.
Tenergy (blue) - >2 Ohm per cell >14 Ohm on battery - GARBAGE!
Tenergy (white)- ~70 mOhm p/c ---- 775 mOhm - PERFECT!
MAHA (black)- ~180 mOhm p/c ----- 1.2 Ohm - NORMAL
BTY - ~70 mOhm p/c -------------- 0.5 Ohm - PERFECT!!! (2 for $5)
GTL - 180-250 mOhm p/c ---------- 1.4 Ohm - NORMAL

Self Discharge.
Tenergy (blue) - 100% for couple months - Unacceptable!
Tenergy (white)- low (LSD)
MAHA -low (LSD)
GTL - LOW (cheap chineese)
BTW - I do not know - new battery...
(I do not measure Self Discharge, evaluate by using battereys inside DMM for long period of time - more then 6 months)