BONAI D Rechargeable Batteries 10,000mAh 1.2V Ni-MH High Capacity High Rate D Size Battery Rechargeable d Cell Batteries high Capacity(8 Pack)

These seem to be great batteries so far. There is a mysterious but consistent event that took place with every single cell when I charged them. The indicators on the Charger displays reached 3 bars, but never 4, which indicates a full charge. I am using a pair of brand new EBL-C9036W chargers and both did the same thing. I left the batteries charging all night thinking that maybe the charging amperage was not what the specs indicated. As it turns out, as far as I can tell, the chargers are working as they should, but the battery indicators were still flashing at 3 bars instead of a solid 4 the next morning. The batteries were almost hot to the touch, but not a dangerous hot by any means, so I unplugged the chargers and installed the batteries in some older, portable fluorescent lanterns. They seem to be undamaged, work great and so far have outlasted any other batteries I have ever used in these lights, including top of the line disposable alkalines. So on to my point and theory. I think each cell has a thermistor installed as a safety device to prevent over charging in the event that someone were to charge them in a manual charger as apposed to a smart charger. When the batteries get warmer than what they are designed for (upon reaching a full charge), the thermistor cuts off incoming or outgoing current to protect each cell. In my case, that would mean the thermistor disconnects each cell before my chargers sense the voltage as fully charged. If this is truly the case, then these batteries are the safest batteries you can buy. Before you ask, I charged some of my Ni-Cad D batteries on these same EBL chargers and they eventually all showed solid, fully charged indicator bars. Ni-Cads are extremely durable and don’t generally require all of the safety measures of other chemistries, as they can handle high heat and overcharging quite well. In general, they can take a beating without self destructing or becoming a fire hazard. If my theory is correct, then I am extremely impressed. This all being said, these batteries are awesome! If you have the same experience, don’t assume that your chargers or batteries are bad. Give enough time for them to reach what should be a full charge based on your charger’s output, then put them to use. These just keep going and going. Very impressed.

I bought these batteries more than 5 years ago, the batteries held their charge for 3 years as advertised for two power outages. Good quality. Would buy again.

Ya, some of the other reviews are right that they don't charge to 10000mah, but I'm happy with 8850mah charge capacity I get. 4 of these will shine my 1000 LUM lantern on high for 12 hours. Cahnge it to low and I get over 24 hours of light. A full charge also delivers near a 1.4 volt level, but it drops quickly to 1.2+ volts in use, but most electronics can handle that in a multiple battery device. I don't know of any battery that takes a full capacity charge. They are always 10%-15% below ratings for the better ones. If you find one that charges to its rated capacity, let me know, otherwise I just think there's a bit of charge left in the battery but not enough to power the electronics or lights. Hence the below rated capacity charging.

I use these batteries for electric candles. I bought (16) of them and after (3) charges (5) of them were no good after only (9) months. I kept getting an error message when charging the batteries. As a result I am suspect to their overall quality. Update July 31, 2020: After dealing with Bonai Customer service rep Jane I had to revise my rating. In as much disappointment as I had with these batteries, I have to say their Customer service was excellent. They immediately got back to me and offered me a free (8) pack of batteries or full credit for what I paid for them. As a result I have revised my 1 star to a 4 star rating. It could have just been a bad batch I had received. The charger's work fine and so far the remaining batteries are working well so I would give them another chance.

easy

I bought these for my ring path lights they take 4 D batteries. It was costing too much for batteries. I use rechargeables for the lights inside my utility trailer so I got these for the outside lights. They seem to be lasting a long time between charges and I don’t see a difference in the brightness. So far it looks like a good buy

So far they seem to work very well. The customer service was very good. one Battery out of an eight pack died after only a month. I contacted their customer service and they sent me a replacement four pack free right away. Also, this has the highest level of man could find. I wanted to really powerful battery. At 10,000 man, this was the highest milliamp I could find.

I purchased 2 sets of these and 2 chargers 2 years ago. They are used only from Thanksgiving to New Year's in window candles. At this point half won't change anymore. The ones that will still charge take 2 days in the same brand charger to charge. That's after less than 3 months actual use. Don't waste your time or money on these. They don't hold up.