Review: Opus BT-C3100 ("dreamcharger!")

1. The charger is oscillating and stops the charging a bit too premature
This has been solved by firmware update: charger will make no current increase back in the CV stage. So no oscillating at all circumstances.

2.The “resting”/overheating periods during 2A charging or 4 × 1A discharge

2A charging is supposed to be used for high capacity Li-ion batteries, we should mention this in user manual that charging with ni-mh AA batteries with 2A charging current is not appropriate. Since 1A discharge current for 4 pcs li-ion batteries will generate a lot heat, and the fan exhausting speed is not fast enough.So it can lead to thermo-protection kicked in, which this safety mechanism is designed for. So I hope it is acceptable. If only two batteries is discharged at 1A speed, it should be no problem.

3. Power spikes from the power supply
We noticed for 9A peak current with very little period time of less than 10ms. we improved this problem by adding a larger enough filtering capacitor and its peak current now is reduced to 7A. The problem is not 100% solved, however it is improving the power supply quality significantly.

4. Uses trickle charging for NiMH when cell is fully charged
I think trickle charging current for nimh is necessary. And we believe this is a good feature of this charger. We have no plan to take this trickle charging away for nimh batteries. For li-ion batteries, there is no trickle charge current.

Thank you, Henry!

Excuse my ignorance on such things, but this says it will discharge, does that mean it will set a charge for storage?

So are the PowerFocus units for sale at Banggood being shipped with the updated firmware?

No, the discharge program will discharge li-ion cells fully (to 2.8V, Ni-MH 0.9V).

It is best to store around 3.7V, so you will need to take the cells out, but you can see the voltage as it discharges.

not yet. the new firmware will show version number 2.0. But I think they will change to new firmware soon because new version has been shipped to them since last week.

How can you tell what firmware is installed on the unit?

when first power up, before full segment is turned on, it will show 2.0 for 2 second.

HKJ wrote Test/Review of Analyzing NiMH/LiIon Charger Opus BT-C3100
showed …

Charger NiMh.

I asked the seller to OPUS …. “–ΔV where is here?”
Dea”OPUS”: This product is no longer available.

What methods CHARGER stop! working?
–ΔV ???
0ΔV ???
1.45v???

Today I received a response.

===
Whom to believe ?
Manufacturer ?
Or pictures HKJ?

Welcome to BLF, Alexp! :party:

It looks like Henry already explained; it uses both negative delta voltage and zero delta voltage (there are temperature sensors too). It is even recommended to use all three in this PDF dated from 2001:
http://www.le.ac.uk/seis-uk/downloads/Charging%20Nickel%20Metal%20Hydride%20Cells%2030.01.01.pdf

This thread may help. It mainly discusses the Maha C9000 which has similar behaviour (and also uses trickle charge).

Anyway, I just charged some slightly discharged Eneloop AAA at 500mA and they terminate past 1.45V but the current was falling from 1.47V, and trickle charge is <24mA.

Thank you. I know it.
OPUS BT-C3100 uses which method at the end of charge NiMh?
I just OPUS BT-C3100 interested.
In HKJ (# 153) was not seen these methods closure charge .

Im wondering if the C and D adapters for models BM200 and Maha C9000 will fit and work on the BT-C3100??

Anyone knows?

Thx.

I mean this ones:
http://www.aliexpress.com/item/2Pcs-Lot-Battery-Adapter-Charge-Test-C-D-Cells-PowerEx-MH-C9000-Charger-or-BM200-Free/1061338631.html

fricco, I believe so. Here are some Powerfocus branded that Banggood are selling, these fit for sure. It shows them in the BT-C3100:

They appear to be the same.

Thanks Chloe!

I ordered the adapters, now just waiting the $41 group gearbest.com to close and oder the charger.

About gearbest.com, i saw that its a new website, opened this year (or at least with last host), its a realiable site?

Thx again!

Explain

Powerfocus BT-C3100 LCD Display Ni-Mh lithium-ion Battery Charger
version V.1 or versions V.2
Thank you.

Henry? What do the owners of BT-C3100 V.1?
As most opus BT-C3100 V.1 alter in BT-C3100 V.2?
Write instruction.
Give advice!

I want to go from my hobby charger that charges 1 cell at a time to a 4-cell at once charger . is this "the charger" to get to replace my hobby charger?

I have both a hobby charger and the C9000. Although a hobby charger and the C9000 have more choices in charging/discharging rates, this one can analyze 4 cells at a time, individually. No need for outboard cradles too.

So has anyone done any experiments using this charger to charge 4 18650 batteries to 4.35 volts?

Who among developers can ask questions? Prompt .