RUKI: I found locally purchased dry batteries being made in China and not lasting long enough.
If anyone (e.g. educational facility, university or just private curious person) would like to run a comparative scientific test - I will be more than happy to volunteer with my 14-20-Channel Battery Capacity Analyser(s)
You supply me with up to 20 batteries of the same voltage and form-factor - whether they are 1.5 (AA or AAA) or 9V does not matter:
I can put them all simultaneously under the same load (can use electronic load) and record "Video of the Race" seeing live which one comes (drains) first.
At the end of the test we will have a comparative graphs/bars of all batteries - voltage and capacity measurements.
We can even make a fun out of it by you putting bids ($1) of which battery comes (drains) first - suggest the winning pool of money goes to the person supplying the batteries and the winner who made the right prediction gets the "wizard" title...
What I am doing when I am in need of the battery for whatever purpose:
- Use of 18650 Li-Ion batteries (have plenty) as a source
- Use DC-DC small form factor step down converters from car chargers (same schematics is used everywhere) which I modify myself (e.g. 3, 5, 4.5, 7,2, 6, 9, 12 V is easy)
- use Velcro self-adhesive to attach battery to device if that can't be inserted inside
e.g. during this Christmas break - I have modified Dolphin Flashlight - converted it into 3-in-1 device by doing this:
- inserted 10 batteries 5P2S x 18650 Li-Ion inside - making it 7.2 10 AH power bank to power my 7.2V cordless drill
- inserted 7805 IC (rated at about 1.5A) with couple of caps and aluminium heat sink inside to convert 7.2 into 5V to power the light bulb (4.8V 0.78A) and 2xUSB sockets
- inserted small power switch and double USB front plug from the old PC for cell phone charging
- inserted temperature sensor and took wires with plugs out for Li-Ion battery balance charging by one of my Li-ion chargers
All above actually was 1/2 day fun creation.
Note: Modification of car charger into any DC voltage takes about 10 minutes...
78XX IC are fixed voltage regulators - can be found in many Telco/IT equipment – the one for this project came from some old network adapter..
This sounds cool and an excellent offer thanks. I am sure this will get lots of attention.
I am happy to buy some of the more expensive batteries. Perhaps lets get a list of the batteries we want to have tested, see who has them already and see who is prepared to sponsor the rest.
I think some of the local brands that have longevity (Not the ones that are imported once under some dodgy name for a sale on 1-day.